‘We couldn’t breathe’: An Israeli city wakes up to carnage.

“Everything’s uncertain,” said Meisam, 41, a poet and writer who joined the crowds of people fleeing Tehran.

The attack on the Quds facility in Tehran, and the extent of any casualties or damage, could not immediately be verified independently. It came as Iranian missiles struck several Israeli cities early on Monday, killing at least eight people, according to Israeli officials.

The volleys were the latest since Israel began attacking Iran on Friday. Since then, Israeli strikes have killed at least 224 people in Iran, according to the country’s health ministry, and injured more than 1,400 people. In Israel, at least 24 people, identified as civilians, have been killed in retaliatory barrages by Iran, with roughly 600 injured.

The attacks have been the longest and most intense in the decades-long enmity between Israel and Iran, raising fears of a wider war that could draw in the United States and other powers.

Israel appears intent on fighting until Iran gives up its nuclear enrichment program, which could be used to create a nuclear bomb, but Iran has given no hint of doing so voluntarily.

The Israeli military said it had struck more than 100 sites in Iran overnight, adding that it was mainly targeting missile launchers. Israeli civil authorities said that Iranian missiles hit at least three residential areas early on Monday — killing five people in central Israel, most of them in the city of Petah Tikva, and three in northern Israel.

Here’s what else to know:

• Life on hold: As the Israeli bombardment continues, some Iranians are steeling themselves for a longer conflict. Israel and Iran have traded fire before in recent years, but this time feels different, some residents of Tehran said. With strikes continuing, long lines of cars have packed a highway in northeastern Tehran as Iranians flee the city.

• Expanding scope of attacks: Israeli strikes, initially focused on nuclear sites, air defenses and military targets, have also begun targeting the energy industry that underpins much of Iran’s economy. The Israeli military’s chief spokesman said its forces had achieved “freedom of action” in the skies over Tehran, but some of Iran’s air defense systems remain intact, according to an Israeli defense official, who spoke on condition of anonymity to discuss sensitive information.

• Trying to get home: Israel’s closure of its airspace to civilian planes since the attacks began has left tens of thousands of travelers stranded overseas. On Monday, Israel said it would start organizing some airlifts — but it may be three days before those flights begin.

• Echoes of strategy: In assassinating numerous top Iranian officers, the Israeli attacks on Iran have seemed to be following the script from last fall, when Israel decimated the Lebanese militia Hezbollah and degraded its military arsenal.

• Damaged diplomacy: Talks between the United States and Iran on the future of Iran’s nuclear program had been scheduled to resume on Sunday in Oman, but were canceled. The Iranian foreign minister, Abbas Araghchi, told foreign diplomats in Tehran on Sunday that his country was “prepared for any agreement aimed at ensuring Iran does not pursue nuclear weapons,” but aims to maintain the right to enrich uranium for civilian purposes.

“There was a huge explosion — more than just a boom,” said Tali Asher, 44, a nurse who lives with her family on the first floor of the building. “The floors and walls shook, the lights went out, and the room was instantly filled with this powdery dust, and we couldn’t breathe.”

The worst destruction occurred two floors above Ms. Asher’s home, but the shock waves from that explosion were still strong enough to cause damage that kept her family trapped inside their apartment until rescue workers pulled them out, Ms. Asher said.

“What we saw was total chaos,” Ms. Asher added. “No windows, broken glass all over the floors, broken metal and our furniture all moved around.”

Ofir Pinsker’s apartment on the third floor suffered a direct hit. “Gone, collapsed,” Mr. Pinsker said as he waited outside later that morning.

He said that his family had survived by sheltering in their fortified safe room — a standard feature in most Israeli homes. But the rest of the apartment was heavily damaged. Mr. Pinsker’s son sat nearby on the curb, next to several grocery bags stuffed with possessions the family had managed to salvage from the wreckage.

Everything else, Mr. Pinsker said, was “buried under broken glass.”

Here’s a look at what the Quds Force is, how it operates, and why it is so important in the escalating clash between Iran and Israel.

What is the Quds Force?

It is an elite unit within Iran’s Islamic Revolutionary Guards Corps, tasked with overseeing the country’s foreign operations and support for proxy groups across the Middle East. Named after the Arabic word for Jerusalem, the Quds Force reports directly to the country’s supreme leader, Ayatollah Ali Khamenei.

The Quds Force has long played a central role in supporting what Iran called the “axis of resistance,” a coalition of militias and political movements across the region that oppose Israel and the United States.

The unit has trained, armed and funded groups including Hezbollah in Lebanon, Hamas in Gaza, Shiite militias in Iraq, and the Houthis in Yemen. Before Israeli offensives severely weakened this regional network, these alliances allowed Iran to exert its influence across the Middle East, shaping the political landscapes of neighboring states in its favor. This included shoring up the Assad regime in Syria and arming Hezbollah to provide a forward line of defense for Iran along Israel’s northern border with Lebanon.

The Quds Force is also believed to have orchestrated operations beyond the Middle East, in Latin America and Europe, according to the U.S. government and intelligence agencies. Activities have included plots to assassinate dissidents, smuggle weapons and conduct espionage targeting U.S. and allied interests.

Who are its leaders?

For more than two decades, the Quds Force was led by Gen. Qassem Soleimani, who spearheaded Tehran’s ambitions to build an axis of military groups across the region to defend Iran’s interests and counter the United States and Israel. Mr. Soleimani was killed in a U.S. drone strike authorized by President Trump in Baghdad in January 2020, dealing a significant blow to the organization.

He was replaced by Gen. Esmail Ghaani, but some analysts say that the unit’s reach and effectiveness has been under strain without General Soleimani’s personal networks and strategic expertise.

How has it fought with Israel?

Before the latest escalation, the Quds Force had been at the center of the long-running covert conflict between Iran and Israel.

The regional adversaries have clashed indirectly through cyberattacks, sabotage operations, targeted assassinations, and maritime attacks. For years, Israel has carried out hundreds of strikes on Iranian-linked targets in Syria — including weapons convoys, drone and missile sites, and military infrastructure. Much of it was operated or supplied by the Quds Force and its allied militias, according to Israeli officials and analysts.

Israel’s assault in recent days has already killed several senior Iranian commanders. A successful strike against the Quds Force — the nerve center of Iran’s military footprint across the region — would represent one of Israel’s most consequential attacks.

Israel launched its attack in the early hours of Friday morning, and the element of surprise was a military imperative.

As a result, Israel abruptly closed its airspace to civilian traffic. Officials said that they could not provide accurate figures for the number of Israelis abroad but estimated that it was 100,000 to 150,000, adding that it was not known how, or when, those travelers might return home. On Monday, the Israeli ministry of defense authorized some rescue flights to begin operating. But it may be three days before the flights start, according to a ministry spokeswoman.

Despite Israel’s long Mediterranean coastline and relative proximity to popular tourism destinations like Cyprus, there are no regular ferry services. The Israeli national security adviser, Tzachi Hanegbi, said that the government was discussing maritime options but that nothing had been decided.

Some stranded travelers were trying to get home via Israel’s land borders with Jordan and Egypt. But the Israeli National Security Council has advised citizens to avoid those routes because of security risks associated with the latest tensions in the region.

The council recommended that Israelis abroad wait for updates from the Ministry of Transportation. The ministry and the Israel Airports Authority said that they were working with airlines to bring citizens home but cautioned that it could take some time.

The Foreign Ministry has asked Israelis abroad to register their details on a digital platform. The expectation was that it could take weeks to bring back all those wanting to return.

Israeli airlines have moved their planes out of the country.

Rachel Brettler and her partner headed for Ben Gurion Airport, near Tel Aviv, on Thursday, to fly out for a six-night vacation on the Greek island of Santorini. They had mused in the taxi about rumors that Israel might attack Iran, Ms. Brettler said, but thought little more of it.

“We couldn’t believe the news when we woke the next morning,” Ms. Brettler said, speaking by phone from Santorini. The couple were planning on going to London, where they have family.

Ms. Brettler said it was “unsettling” to be away from their home in Herzliya, north of Tel Aviv, at a time like this. They were still receiving missile alerts from Israel on their cellphones.

Travel in and out of Israel had already been severely curtailed after the Hamas-led attack of Oct. 7, 2023, which ignited the war in Gaza. Many international airlines had suspended flights to and from the country.

Amid the travel upheaval, some visitors have also found themselves stuck in Israel.

Myra Noveck contributed reporting from Jerusalem.

Israel targeted the Natanz fuel enrichment plant on Friday and destroyed the above ground part of the pilot fuel enrichment plant, but the level of radioactivity outside the site “has remained unchanged and at normal levels,” Rafael Mariano Grossi, head of the U.N. agency, said in a statement to its board of governors.

The Israeli military also said that it had killed four more senior Iranian intelligence officials, including the head of intelligence for the Revolutionary Guards. Those claims could not be independently confirmed and there was no immediate comment from the Iranian authorities.

Israel seems motivated to continue until the destruction of Iran’s nuclear enrichment program, either by force or renewed negotiations. Yet Iran has shown no sign of voluntarily ending enrichment, a process crucial to building a nuclear bomb, and Israel has no known ability to destroy a pivotal enrichment site that is buried deep underground.

“We’re weeks rather than days away from this ending,” said Daniel B. Shapiro, who oversaw Middle Eastern affairs at the Pentagon until January.

“Israel will keep going until, one way or another, Iran no longer retains an enrichment capability,” added Mr. Shapiro, now a fellow at the Atlantic Council, a Washington-based research group. “It’s now clear that if Israel leaves this unaddressed, its campaign will have failed.”

While Israel has easily struck Iran’s main enrichment site at Natanz, central Iran, it lacks the American-made “bunker-buster” bombs needed to destroy a smaller subterranean site dug deep into a mountain near Fordo, northern Iran. Israeli officials hope that their strikes on other targets — including Iran’s top military commanders, nuclear scientists and its energy industry — will inflict enough pain to encourage Iran to willingly end operations at Fordo.

For now, Iran seems far from such a capitulation, even if Israel has shown increasing dominance in Iranian airspace, according to Sanam Vakil, who leads analysis of the Middle East at Chatham House, a London-based research group. Though Israel hopes to prompt its collapse, the Iranian government remains in full control of Iran and still has substantial stocks of ballistic missiles, even if Israel has limited its ability to fire some of them.

“I don’t see any surrender coming from Tehran right now — there are no white flags being waved,” said Dr. Vakil. “It’s very hard to see Iran walking back its enrichment rights while Iran’s program still looks operational and Iran is intact as a state,” she added. “Their goal is to survive, to inflict damage and show their resilience.”

Much depends on how President Trump reacts. Unlike Israel, the United States has the munitions and the aircraft to destroy Fordo. Analysts like Mr. Shapiro say that Mr. Trump could consider such an approach if Iran chooses to accelerate its efforts to build a nuclear bomb instead of reaching a compromise.

“That will create a critical decision point for Trump, about whether the United States should intervene,” Mr. Shapiro said.

It may also now be easier for Mr. Trump to intervene without serious security consequences, given that Israel’s attacks have already degraded Iran’s defensive abilities.

Others say that Mr. Trump is likelier to avoid direct confrontation with Iran unless the Iranian military shifts its attacks from Israel to U.S. interests and personnel in the Middle East, narrowing Mr. Trump’s room for maneuver. Since Friday, Iran has avoided providing such a pretext for U.S. involvement, and has also avoided attacks on the U.S.’s other allies in the region, including Saudi Arabia and the United Arab Emirates.

The president’s statements since Friday indicate that his current preference is to use Israel’s military gains as leverage for renewed talks with Tehran.

For months, Mr. Trump has overseen negotiations with Iran, hoping that Tehran would agree to end its enrichment program without Israel’s military intervention.

Those talks stumbled after Iran refused to back down. In comments over the weekend, Mr. Trump suggested that Iran, chastened by Israel’s attacks, might finally make compromises that its had not previously considered. As a result, some analysts say that Mr. Trump could press Israel to end its attacks — when and if he judges that Iran has become more malleable.

“This will end when Trump decides to end it, which will probably happen when he thinks Iran is ready to compromise,” said Yoel Guzansky, an expert on Iran at the Institute for National Security Studies in Tel Aviv.

Such a U-turn has historical precedent, even if it feels unlikely for now, experts said. The Iranian leadership made a similarly unexpected compromise at the end of the Iran-Iraq war in the 1980s, according to Meir Javedanfar, who teaches Iranian studies at Reichman University in Israel. After rejecting numerous offers to end the war, Ayatollah Khomeini eventually agreed to a deal after the costs of the war became too great, Dr. Javedanfar said.

“Khomeini made a 180-degree change,” he said. “This is again what Israel is hoping for.”

But history also suggests this may take time. The deal that ended the Iran-Iraq war took eight years to reach.

Gabby Sobelman in Rehovot, Israel; Myra Noveck in Jerusalem and Johnatan Reiss in Tel Aviv contributed reporting.

Sigal Kovalski, 47, who lives in Petah Tikva, said that she and her family heard an explosion and saw dust trickling into the room where they were sheltering. When they emerged, they found their apartment completely ruined.

“The windows were broken, the floor was covered with shattered glass and the furniture was in pieces,” she said.

Photos and videos from Petah Tikva showed a high-rise residential building with several floors blackened and visibly blown outward, with concrete and debris dangling from the blast site.

Nearly 100 people were injured across central Israel on Monday, including in Haifa and Tel Aviv, and search and rescue operations were continuing, according to Magen David Adom, the national emergency service.

Iranian missiles also hit Israel’s largest oil refinery, in Haifa Bay in northern Israel, according to footage verified by The New York Times. Firefighters were trying to contain a blaze ignited by the strike and to rescue people trapped in the area, said Tal Volvovitch, a spokeswoman for the Israel Fire and Rescue Authority.

The attacks followed a day of strikes on multiple locations in Iran and Israel, including a rare daytime Israeli air raid on Tehran that caused casualties and damage to buildings and infrastructure. Internet traffic from Iran dropped significantly, according to NetBlocks, an internet monitoring group. That left many Iranians unable to contact emergency services or connect with the outside world.

The fighting, which began on Friday with an Israeli attack on Iran, has been the fiercest and most prolonged between Israel and Iran in decades. It has stoked fears of a wider regional conflict that could draw in the United States and other powers.

The Israeli strikes have killed at least 224 people in Iran, according to the country’s health ministry. Several top Iranian security chiefs are among the dead, and more than 1,400 people have been injured.

In Israel, at least 21 people have been killed in Iran’s retaliatory barrages since Friday, according to the national emergency service.

“My biggest concern is nothing other than radioactive leaks and the bombing of areas that have nuclear facilities. I haven’t personally received any official guidance,” Ilya, 28, from the city of Karaj, near Tehran, said via text. Ilya asked to be identified only by his first name for security reasons.

The surprise attacks on Iran, which began on Friday, have highlighted the country’s apparent lack of preparedness for war — including its paucity of shelters, bunkers or functioning air-raid sirens. Without much clear direction from the government, Iranian musicians, artists, chefs and influencers have been sharing infographics on social media with titles including “What You Should Do if You’re in the Metro During an Airstrike” or “How to Speak to Children in War Times.”

Several people in Iran whom The New York Times messaged and spoke with said they were unsure whether to go to work or whether students should go to school — a fraught dilemma at the height of final exam season.

Many Iranians are unsure of what information they can trust and what to believe — regardless of whether it comes from the government or from unofficial channels.

“I keep seeing Instagram stories with guidance and information but they don’t have a clear source and are pretty scattered,” Ilya said. He added:

“Honestly, I don’t know which ones are accurate and which aren’t, because it’s all scattered and unclear, and everyone seems to have their own opinion.”

In family WhatsApp groups, confusion abounded. Many comments came from Iranian women who cited their experience during the Iran-Iraq war in the 1980s, offering tips to distinguish the sounds of strikes from those of air-defense interceptions, to help inform their current situation. Other people have struggled to access the internet, with communication networks in the country increasingly spotty.

On Sunday, the third consecutive day of Israeli attacks, the Iranian government stressed that measures were being taken to protect the population.

“Mosques are shelters for all people, and starting tonight, the metros will also open so that people can have access to safe spaces 24/7,” said Fatemeh Mohajerani, a government spokeswoman, referring to Tehran’s rapid transit system, which is mostly underground. In remarks carried by Iranian news media, she added that many schools could also be used as shelters.

It was unclear, though, how many people would be reassured. Long lines formed at gas stations in Tehran, the capital, and the city’s roads were choked with traffic as terrified families scrambled to leave.

In Isfahan, a city in central Iran that has been struck by the Israeli military campaign, one woman, Farangis, said she tried on Saturday night to convince a friend to join her in leaving the city for a village further south.

“Just like last time,” Farangis, who is in her 70s, said she told her friend. That was all that Farangis, who for security reasons asked that only her first name be used, needed to say: Decades ago, both women had fled their homes when Iraq was bombing Iran.

But her friend refused, Farangis said, saying that she could not leave her children and grandchildren — who had “school and work that doesn’t seem to have been canceled.”

A few hours later, a spokesman for the Israeli military posted a photo of a plane at the same location engulfed in flames and confirmed the military had attacked the airport. “The Air Force is operating to achieve aerial superiority across all of Iran,” he said in the statement.

The location of the attack, at Mashhad Airport in the far east of the country, shows “at the very least that Israel can hit just about any target it wants in Iran,” said Afshon Ostovar, an Iran military expert at the Naval Postgraduate School in Monterey, Calif.

Dr. Ostovar added that the attack is a sign “that most if not all of the country’s major air defenses have either been destroyed, made inoperable, or are otherwise unable to protect Iran’s airspace from Israeli jets.”

The Iranian Air Force only has seven refueling planes, according to a 2024 annual report on air forces globally by FlightGlobal, an aviation industry website.

But Dr. Ostovar said that taking the plane out will not affect Iran’s air operations. These aircraft — which are Boeing 707s — are used to refuel fighter jets and other planes while they’re in the air, which Dr. Ostovar said Iran does not currently do.

But the strikes have not yet meaningfully affected the flow of oil in the region, which is a key energy transit hub, said Tom Kloza, chief market analyst for Turner, Mason & Company, an energy consulting firm.

Oil prices gained about 11 percent last week. That alone could cause gasoline prices to rise about 20 cents a gallon in the coming weeks, according to ClearView Energy Partners, a Washington research firm.

Crude oil and fuels like gasoline and diesel had been relatively cheap leading up to Israel’s strikes on Iran, which could cushion the blow to consumers. A gallon of regular gasoline costs $3.14 on average, down from $3.45 this time last year, according to the AAA motor club.

How Iran responds to Israel’s latest strikes will have a big effect on oil prices. The country is a large oil producer and its position on the northern side of the Strait of Hormuz, a major thoroughfare for oil and liquefied natural gas, or L.N.G., means that it could severely disrupt global energy markets.

If Iran were to close the waterway connecting the Persian Gulf to the Gulf of Oman for even a short time, oil prices could rise anywhere from $8 to $31 a barrel, according to ClearView Energy Partners.

“Escalation of the conflict presents many supply risks, but — at peril of stating the obvious — the greatest is probably an Iranian closure of the Strait of Hormuz to maritime energy cargoes,” the firm’s analysts wrote on Saturday.

Iran has an economic incentive to allow tankers to continue passing through the strait, as it ships oil through that channel, much of it to China.

And although the United States has been buying less and less oil from the Persian Gulf, the commodity is traded globally, leaving consumers and businesses exposed to price increases. Should U.S. oil companies respond to higher prices by drilling more, it would still take many months for that oil to start flowing.

Farnaz Fassihi contributed reporting.

“We have opened up the skies of Iran, achieving near-air superiority,” Yechiel Leiter, Israel’s ambassador to the United States, said on social media.

Still, Israel does not have complete freedom of operation in Iran, and Iranian officials have claimed to have shot down Israeli drones in recent days.

Some of Iran’s air defense systems remain intact, requiring Israeli pilots to navigate through carefully mapped aerial corridors, according to an Israeli defense official, who spoke on condition of anonymity to discuss sensitive information. The Israeli military, the official said, relies on real-time intelligence to track possible threats to its aircraft as they enter and exit Iranian airspace.

At least 128 people in Iran have been killed, according to the country’s health service. The toll included top security chiefs, nuclear scientists and civilians.

Opening up Iran’s airspace was a gradual process. During two clashes with Iran in April and October of last year, Israeli security forces struck important air-defense systems. In the October attack, Israel hit four S-300 systems, according to Yoav Gallant, the Israeli defense minister at the time.

Since Friday, Israel has continued to target Iran’s air defenses, carving out a pathway for Israeli fighter jets to reach Tehran freely, according to two Israeli military officials, who spoke on condition of anonymity to discuss operational details. Prime Minister Benjamin Netanyahu told Fox News in an interview on Sunday that Israel had worked to “peel off the layers of protection” of Iranian defenses.

Israeli aircraft, in turn, now have the ability to fly through much of Iranian airspace almost as easily as they can over Lebanon and Syria, according to Zohar Palti, a former senior official in Mossad, Israel’s foreign intelligence service.

“Let’s say I have a target that I missed or that I’m not happy with the result,” said Mr. Palti, now an international fellow at the Washington Institute for Near East Policy. “I can go back tomorrow and the day after tomorrow again, again, and again.”

Even Iranian officials have acknowledged shortcomings in their defenses.

In private text messages shared with The New York Times on Friday, some officials were angrily asking one another, “Where is our air defense?” and “How can Israel come and attack anything it wants, kill our top commanders, and we are incapable of stopping it?”

Farnaz Fassihi contributed reporting to this article.