Israel widens targets in another series of strikes on the Iranian capital.

The strikes came despite calls from world leaders for both sides to ease their attacks, even as President Trump’s decision to join Israel’s campaign against Iranian nuclear sites raised fears that the war would escalate. American military and intelligence officials detected potential signs that Iran-backed militias were preparing to attack American bases in Iraq, and possibly Syria.

Iranian officials appeared to be weighing their options for retaliation against the United States, as Iran’s foreign minister, Abbas Araghchi, met with a key ally, President Vladimir V. Putin of Russia. But the Russian leader stopped short of offering concrete support for Iran. And more than 36 hours after the American attacks, Iran’s supreme leader, Ayatollah Ali Khamenei, who will have the final say in any response, had yet to make an official statement.

Though Mr. Trump declared that Iran’s nuclear program had been “totally obliterated” by the U.S. bombings, the actual state of the program seemed far more murky, with senior officials conceding they did not know the fate of Iran’s stockpile of near-bomb-grade uranium.

Trump administration officials emphasized on Sunday that the United States did not want an all-out war with Tehran, but Mr. Trump’s position was less clear — particularly when he raised the prospect of regime change in Iran in a social media post on Sunday. He was set to meet with his National Security Council on Monday.

Here’s what else to know:

• Calls for peace: After European foreign ministers met to discuss Iran, the European Union’s chief diplomat, Kaja Kallas, said that “the concerns of retaliation and this war escalating are huge.” The International Atomic Energy Agency held an emergency meeting in Vienna, where the head of the agency, Rafael Grossi, warned that “violence and destruction could reach unimaginable levels” if Iran, Israel and the United States do not find a path to diplomacy.

• Possible response: Mr. Trump’s decision to attack Iran seemed likely to dim hopes for a negotiated solution to end the fighting, only days after the president had indicated he would wait for as long as two weeks to give diplomacy a chance. While U.S. officials say that Iran has depleted its stockpile of medium-range missiles, the country still has an ample supply of other weapons, including rockets and drones.

• The strikes: Pentagon officials described a tightly choreographed operation that included B-2 bombers carrying 30,000-pound bunker-buster bombs and submarine-fired Tomahawk cruise missiles hitting a trio of sites in less than a half-hour. A senior U.S. official acknowledged that the attack on Fordo had not destroyed the heavily fortified site, but it had been severely damaged.

• Economic impact: Asian markets dipped on Monday, reflecting investor concern over possible economic fallout from the U.S. strikes and any potential moves by Iran to disrupt shipping through the Strait of Hormuz, a critical transit point for global oil supplies.

River Akira Davis contributed reporting.

Since launching its campaign against Iran earlier this month, the Israeli military has hit Iranian nuclear facilities, scientists and senior military commanders, but it has also struck targets lacking a clear link to Iran’s nuclear program or ballistic missiles, including the state broadcaster.

According to the defense minister’s office, Israel’s strikes in Tehran on Monday targeted the headquarters of the Basij, a volunteer force under the umbrella of the Islamic Revolutionary Guards Corps that has used brutal tactics to crack down on protests in Iran, and Evin prison, the notorious facility holding political prisoners.

Israel also struck access routes to Fordo, the heavily fortified nuclear-enrichment site that the United States bombed on Sunday, the Israeli military said.

President Trump claimed on Sunday that Iran’s nuclear program had been “totally and completely obliterated.” Prime Minister Benjamin Netanyahu of Israel said that the American military caused “very big damage” to Fordo, but he clarified that Israel still did not know the full extent.

Morteza Heidari, the spokesman for crisis management in the province where Fordo is, on Monday reported an “attack on the Fordo nuclear site,” according to the government-affiliated Mehr and Tasnim news agencies. He said there was no danger to the public from the strikes, the news agencies said.

Later on Monday, the Israeli military said it had targeted other forces under the Revolutionary Guards, including ones that it described as being responsible for dealing with domestic threats. It also said it had hit missile and radar production sites and missile storage infrastructure.

The impact and extent of the strikes were not immediately clear. But videos verified by The New York Times showed the moment of the blast at an entrance into the Evin prison, and clouds of smoke emanating from a metal gate below a sign that reads ‘Evin Detention Facility’ in Farsi.

The reports of the strikes on the Evin prison caused particular concern in France because two French citizens, Cécile Kohler and Jacques Paris, are detained there.

“We are worried that Cécile and Jacques are going to die under bombs,” Noémie Kohler, Ms. Kohler’s sister, told Franceinfo radio on Monday. “We still have no way of contacting them,” she added. “We are absolutely panicked.”

France has accused Iran of detaining Ms. Kohler and Mr. Paris for over three years on baseless spying charges and has repeatedly demanded their release.

The strikes on Evin — which is close to apartment blocks and a popular hiking route — also hit a main power line that caused outages in two large districts of Tehran, according to the national electricity company Tavanir. It said in a statement distributed broadly to government-affiliated news agencies that it was able to repair the outages within an hour.

Iranian news outlets also reported that the Israeli military hit a building near the Iranian Red Crescent Society, an emergency response service. A video posted by the government-affiliated Mehr news agency, and verified by The Times, showed smoke rising in the area. It was not clear what was in the building that had been struck.

Erika Solomon and Sanjana Varghese contributed reporting to this article.

“We are advancing, step by step, to achieve these goals,” he said. “We are very, very close to completing them.”

Mr. Netanyahu did not say when he believed Israel would end its bombing campaign. Nor did he mention another goal that some observers have suggested Israel might be pursuing in Iran: regime change.

Israelis have broadly backed Mr. Netanyahu’s decision to open the offensive against Iran. Even longtime critics of the prime minister — including Yair Lapid, head of Israel’s parliamentary opposition — have praised what they see as the war’s tactical successes.

But as Iran launches missiles in response, the conflict has also paralyzed much of Israel, shuttering schools, businesses and the international airport near Tel Aviv, leaving thousands of Israelis stranded abroad. The economic damage has compounded the cost of more than 20 months of war in Gaza and Lebanon.

Some Israeli analysts and politicians have argued that now is the time to wind down the fighting.

In his address on Sunday night, Mr. Netanyahu said that he would not be dragged into a “war of attrition” with Iran. But Israel would not cease its assault on Iran before it had “accomplished all of its goals,” Mr. Netanyahu vowed, without providing a timetable.

“We will not continue to operate beyond what is necessary to achieve them,” he said. “But we also won’t finish up too soon. When the aims are achieved, the operation will be concluded, and the fighting will stop.”

Some analysts in Israel have suggested that if Mr. Netanyahu’s war against Iran is seen as successful, he could show greater flexibility in talks to end the war with Hamas in Gaza and to free the remaining hostages there. For months, Mr. Netanyahu has seemed unwilling to make concessions in the talks, which his far-right political allies have opposed.

On Sunday, Mr. Netanyahu said that the blows dealt to Iran — a longtime patron of Hamas — would also further weaken the Palestinian armed group in Gaza.

“It will take a bit more time. But there’s no doubt that our great achievements in Iran contribute to achieving the goals in Gaza,” he said.

“The absolutely unprovoked aggression against Iran is unfounded and unjustified,” Mr. Putin said at a meeting with Iran’s foreign minister, Abbas Araghchi, according to a Kremlin statement. “We are making efforts from our side to provide support to the Iranian people.”

Mr. Putin told Mr. Araghchi that he had spoken about the Israel-Iran war with President Trump, as well as with the leaders of Israel, Iran and the United Arab Emirates. Earlier on Monday, the Kremlin said Mr. Putin also spoke by telephone with Prime Minister Mohammed Shia al-Sudani of Iraq.

The discussions appeared to be part of the Kremlin’s broader efforts to present Russia as a potential mediator in any talks that could bring an end to the fighting.

“Going forward, everything will depend on what Iran will need,” Mr. Peskov said.

He added that Russia had already issued a statement condemning strikes on Iran, and had offered to mediate the conflict.

“These are types of support,” Mr. Peskov said.

The review referred to a number of issues that could have constituted a breach of Israel’s obligations. Those included Israeli restrictions of essential goods and food into Gaza, attacks that the report said had caused a “significant number of casualties,” and military strikes on hospitals and medical facilities.

Under the terms of the treaty, the European Union and Israel agreed that their relationship “would be based on respect for human rights and democratic principles.”

European Union member states are sharply divided on Israel, meaning that a major shift in policy may be hard to pass. But the report’s conclusions underscored growing frustrations, including among some of Israel’s closest allies, over the handling of the war in Gaza.

Kaja Kallas, the European Union’s foreign policy chief, was expected to present the findings of the review to a meeting of the bloc’s foreign ministers in Brussels on Monday. The conclusions from the review were circulated among member states on Friday.

Israel strongly rejected the findings. The Israeli Foreign Ministry said in a response to the European Union, shared with The Times, that the review was “a complete moral and methodological failure,” and pointed out that it “opens with an admission that it lacks the ability to verify its own statements.”

Israeli officials defended the restrictions on aid as security measures intended to prevent Hamas from smuggling weapons or diverting aid supplies. The United Nations and other international aid agencies have criticized some of the measures as a form of collective punishment, and they say that Israel has not provided evidence that Hamas systematically diverted international aid.

The back-and-forth underscored how tense relations between the European Union and Israel have become. The situation has become more complicated after Israel launched a major assault on Iran last week, one that now involves the United States. Israel and the United States say the military attack was intended to prevent Iran from developing a nuclear bomb. Iran says that its nuclear program is for civilian purposes only, and has denied building a weapon.

E.U. officials have spoken about the conflict with Iran cautiously. Some have spoken more positively about the Israeli and American attacks, while others have held off. Many have urged a return to diplomacy to resolve the crisis.

“Everybody agrees that Iran should not have a nuclear weapon,” Ms. Kallas said on Monday as she headed into the foreign ministers’ meeting, before explaining that officials would talk both about Iran and about the report on Israel.

“And then, of course, the discussion is, what more can we do?” Ms. Kallas said of the Israel review.

Finding Israel in violation of its human rights obligations under its agreement with the European Union would be symbolically important, but it is not clear what it would mean in practical terms. Imposing sanctions, for instance, would require unanimity among member states — which is unlikely to be reached. The prime minister of Hungary, Viktor Orban, for example, is an ally of Mr. Netanyahu and would almost certainly not agree to impose restrictions on Israel.

The review has also been overshadowed by events in Iran. Some European officials and diplomats have said that the conflict with Tehran should not distract from what is happening in Gaza, but the combination of events has left Brussels struggling to agree a unified stance toward Israel.

Ursula von der Leyen, president of the European Commission, the European Union’s executive arm, announced on Sunday that officials would hold a special meeting on Wednesday to discuss the “escalating situation in the Middle East and its effects on Europe.”

“We may not agree on the reasons behind and even the consequences of the current crisis, but there is a common denominator that exists,” he said at the meeting of the watchdog, the International Atomic Energy Agency. “First, we don’t want to see a nuclear accident.”

Israel began its military campaign against Iran’s nuclear program and military leadership on June 13. The United States intervened militarily early on Sunday local time, attacking the three Iranian nuclear sites, with President Trump saying that the goal was to prevent Iran from building a nuclear weapon.

American officials have said that while Israel’s intelligence agency believes that Iran can achieve a nuclear weapon in 15 days, American spy agencies believe that it could take several months, and up to a year, for Iran to make a weapon.

The International Atomic Energy Agency declared on June 12 that Iran was not complying with its nuclear nonproliferation obligations. But Mr. Grossi stressed on Monday that the correct approach was diplomacy, and urged a return to negotiations.

“Military escalation not only threatens lives, it also delays us from taking the diplomatic path to achieve the long-term assurance that Iran does not acquire a nuclear weapon,” Mr. Grossi said Monday. Iran insists that its nuclear program is for civilian use, not to develop weapons.

“There has never been a time more important than now to muster the political courage to step away from the edge,” Mr. Grossi said.

Later on Monday, the Israeli military said that it had attacked access routes to the Fordo nuclear enrichment site to obstruct them, a day after the United States struck the site itself. Both Israeli and American officials have said the site was severely damaged in Sunday’s U.S. strikes, but that it would take time for a full damage assessment.

Mr. Grossi said that at this time “no one, including the I.A.E.A.,” is in a position to has fully assessed the damage at Fordo. He added that Iran has informed the agency that there was no increase in off-site radiation levels at any of the three sites hit by the United States.

Senior American officials have conceded that they do not know the fate of Iran’s stockpile of near-bomb-grade uranium. Mr. Grossi said on Monday that Iran’s foreign minister, Abbas Araghchi, had written in a June 13 letter to him that Iran would adopt “special measures” to protect nuclear equipment and materials.

Aaron Boxerman contributed reporting.

In the original post, according to a screenshot by the local TV news station KTLA, the department said “Our hearts go out to the victims and the families impacted by the recent bombings in Iran.”

In its statement on Sunday, the Sheriff’s Department called that post “offensive and inappropriate.”

“This post was unacceptable,” the Sheriff’s Department said, “made in error, and does not reflect the views of Sheriff Robert G. Luna or the Department.”

As a law enforcement agency, the Sheriff’s Department said, it did not comment on “foreign policy or military matters.” It said it was conducting an internal investigation to determine how the post was created and published.

Los Angeles County is home to large populations of both Iranian and Jewish people, including many Iranian Jews.

Of the roughly 400,000 Iranian-born immigrants in the United States, roughly one-third lives in or around Los Angeles, according to the Migration Policy Institute. Westwood, a neighborhood on the west side of Los Angeles near the U.C.L.A. campus, has been nicknamed “Tehrangeles.”

Los Angeles is also home to more than 500,000 Jews, the second-largest Jewish community in the U.S., according to 2021 research by Brandeis University.

The Sheriff’s Department’s social media post emphasized that there was no specific danger for residents but encouraged people to be vigilant.

“At the moment, there are no known threats to Los Angeles County. However, out of an abundance of caution, we are increasing patrol checks at places of worship and other sensitive locations throughout the county,” the sheriff’s department said.

“Ministers are very much focused on the diplomatic solution, and also the concerns of retaliation and this war escalating are huge,” Kaja Kallas, the European Union’s top diplomat, told journalists. Ms. Kallas added that any Iranian closure of the Strait of Hormuz, a key shipping route for oil and gas, would be “extremely dangerous.”

American military and intelligence officials have detected signs that Iran-backed militias were preparing to attack American bases in Iraq, and possibly in Syria, in retaliation for the U.S. strikes in Iran on Sunday, fueling fears that tensions could ramp up. If Tehran were to close access to the Strait of Hormuz, oil prices could soar and some U.S. Navy ships could be pinned in the Persian Gulf, American military officials say.

Ms. Kallas and foreign ministers from Britain, France, and Germany met with Iran’s foreign minister, Abbas Araghchi, in Geneva on Friday. Ms. Kallas said that at that meeting, Iran was opening up to discussions of “nuclear, but also broader security issues that are concerning Europe.”

Still, officials fretted that a peaceful outcome remained far from guaranteed.

“We are very concerned about the risk of an escalation, which could be devastating in the Middle East and have very serious consequences for the stability of the world,” Jean-Noël Barrot, France’s minister for Europe and foreign affairs, said as he headed into Monday’s meeting.

“Europe can bring its experience, its competence, in-depth knowledge of these questions to open a space for negotiation,” he added.

While Mr. Barrot and other European officials suggested that strikes on Iranian nuclear facilities by Israel and the United States might delay nuclear developments, they also said that a negotiated solution would be more durable in the long run.

“At this moment, I think it’s very important to find a way back to the negotiations,” Caspar Veldkamp, the Dutch minister for foreign affairs, told reporters.

Videos verified by the New York Times showed an explosion today at the entrance to Evin Prison, a notorious detention facility on the outskirts of Tehran where hundreds of dissidents and political prisoners are held. Footage shows the moment of the blast at an entrance into the prison compound, and large clouds of smoke emanating from a metal gate below a sign that reads ‘Evin Detention Facility’ in Farsi. Another video, distributed by the Iranian broadcaster Iran International, is filmed from a car driving on the highway directly adjacent to the compound and shows plumes of smoke continuing to rise from the area.

Iranian news outlets reported that Israeli strikes hit a building beside to the Red Crescent Society in the capital Tehran. A video posted by the government-affiliated Mehr news agency, verified by the New York Times, showed white smoke billowing up in front of the building.

Saying that “military escalation not only threatens lives, it also delays us from taking the diplomatic path to achieve the long term assurance that Iran does not acquire a nuclear weapon,” Grossi also offered to travel immediately to Iran and to engage with all parties involved to help ensure the protection of nuclear facilities.

In more than a week of fighting between Israel and Iran, Israel’s military has steered clear of hitting Iranian naval assets. So while Iran’s ability to respond to attacks has been severely damaged, it has a robust navy and maintains operatives across the region, where the United States has more than 40,000 troops. Iran also has an array of mines that its navy could lay in the Strait of Hormuz, which hugs a portion of Iran’s southern border.

A quarter of the world’s oil and 20 percent of the world’s liquefied natural gas passes through the Strait of Hormuz, so mining the choke point would cause oil and gas prices to soar. The majority of those fuels go to Asia, meaning that countries there would most likely be severely affected by any closure. The United States and other countries would feel the effects in the form of higher energy costs.

Closing the waterway could isolate American minesweepers in the Persian Gulf on one side of the strait. Two defense officials indicated that the Navy was looking to disperse its ships in the gulf so that they would be less vulnerable. A Navy official declined to comment, citing operational security. The officials spoke on condition of anonymity because they were not authorized to speak publicly.

Even before the U.S. military struck Iranian nuclear sites over the weekend, Iran vowed that it would respond forcefully to any attack by American forces — potentially setting off a cycle of escalation. Since the strikes, Iran appears to be weighing its options.

“Iran is strategically weaker but operationally still lethal across the region, and Americans still have troops across that part of the world,” said Brian Katulis, a senior fellow at the Middle East Institute.

Military officials and analysts said missile and drone attacks remained the biggest retaliatory threat to U.S. bases and facilities in the region. Some also worry that the Quds Force, a shadowy arm of Iran’s military, could attack U.S. troops.

Much is at stake for Iran if it decides to retaliate. “Many of Iran’s options are the strategic equivalent of a suicide bombing,” said Karim Sadjadpour, an Iran policy expert at the Carnegie Endowment for International Peace. “They can do enormous damage to others if they mine the Strait of Hormuz, destroy regional oil facilities and rain a missile barrage against Israel, but they may not survive the blowback.”

But Iran can make it hugely expensive, and dangerous, for the U.S. Navy to have to conduct what would most likely be a weekslong mine-clearing operation in the Strait of Hormuz, according to one former naval officer who was stationed on a minesweeper in the Persian Gulf. He and other Navy officers said that clearing the strait could also put American sailors directly in harm’s way.

Mining the strait would also inflict severe economic damage in Iran because nearly all of the country’s oil exports move through the channel.

In the battle for global narratives, China has long cast the United States as a warmonger and a destabilizing power while presenting itself as a responsible global leader championing peace and fairness.

At an emergency meeting of the Security Council on Sunday, Mr. Fu said that China condemned the U.S. strikes and was joining Russia and Pakistan in drafting a U.N. resolution calling for a cease-fire, the safety of civilians and a start to peace negotiations.

The criticism of the United States was echoed in Chinese state media reports on Monday, with the official news agency, Xinhua, accusing the United States of escalating violence in the region.

“The worsening situation in the Middle East is a stark reminder that power politics and military interventions lead to nothing but chaos and instability,” the article said.

In a separate editorial on Monday, the Communist Party tabloid, the Global Times, said the U.S. strikes had weakened “the foundation of the international security order.”

On China’s heavily censored internet forums, users have left furious comments about how Iran was deceived into thinking it was negotiating a nuclear agreement with the United States, only to lower its guard and become the target of U.S. bombs.

China’s rhetoric belies a more complicated reality. Beijing has been one of Tehran’s biggest backers, diplomatically and economically. Its purchases of almost all of Iran’s oil exports have helped a brutal Iranian regime stay in power and deliver support to its terrorist proxies abroad, including Hamas, Hezbollah and the Houthis.

It remains to be seen how China might use its influence over Iran as fears of a broader conflict grow. Secretary of State Marco Rubio on Sunday urged China to persuade Tehran not to make good on a threat to close the Strait of Hormuz, one of the world’s most vital waterways for the transport of oil.

“China will certainly oppose Iran” closing the strait, said Wang Yiwei, the director of the Institute of International Affairs at Renmin University in Beijing, because of China’s need for access to Iranian oil. But it would only do so on its terms and in its own time, he suggested.

“However, it would be improper, or even counterproductive, to discuss this with the United States, or to exert pressure on Iran at the request of the United States,” he added.

When asked on Monday what China would do if Iran closed the strait, Guo Jiakun, a spokesman for the Foreign Ministry, deflected and called on the international community to “step up its efforts to promote the de-escalation of the conflict.”

Sirens are now wailing in central Israel in response to additional missile fire, according to the Israeli military.

Israeli fighter jets attacked surface-to-surface missile launchers and storage sites in Kermanshah, the military later said, calling it part of Israel’s broader aim of degrading Iran’s military capabilities.