Iran was reeling and firing missiles and drones Friday after Israel carried out its largest attack ever against the regime in Tehran, waves of coordinated airstrikes that hit nuclear sites and killed much of the country’s military chain of command along with several nuclear scientists.

Israel’s assault early Friday and Iran’s response immediately raised the prospect of a wider conflict engulfing the Middle East, although Iran’s military capabilities and its proxy militias have been weakened by 20 months of Israeli attacks.

Israeli Prime Minister Benjamin Netanyahu described the assault as a last resort to prevent Iran from obtaining a nuclear weapon, which Israel calls an existential threat, and he vowed that the attacks would last “as many days as it takes.”

Iran’s supreme leader, Ayatollah Ali Khamenei, said in a televised statement Friday that Iran would act forcefully to punish Israel for the attack. “Life will be dark for them,” he said. “They started it. They started a war.”

Iran’s foreign minister, Abbas Araghchi, told the United Nations Security Council on Friday that Israel’s strikes had killed 78 people and injured 329 others.

In response, Iran fired “fewer than 100” missiles in two waves toward Israel on Friday, most of which were intercepted by Israel’s robust air defenses, according to Brig. Gen. Effie Defrin, an Israeli military spokesperson.

But several buildings were hit, some with shrapnel.

At least 40 people were wounded in Tel Aviv, Israel, and the surrounding area, according to a tally from three hospitals. Most of the patients were moderately injured, but a few were in critical condition.Iran’s Revolutionary Guard said it had struck dozens of targets in Israel “forcefully and with precision,” including military and defense sites, in response to Israel’s attacks.

The Israeli military said that Iranian forces had also launched about 100 drones at Israel and that a missile fired from Yemen had landed in the Israeli-occupied West Bank. Israel said it had shot down many of the drones, and there were no immediate reports of casualties.

Israel’s attack was an audacious attempt to cripple a country that it has been battling for years, with covert operations aimed at killing Iran’s military commanders and nuclear scientists, and direct combat against forces it supports across the Middle East, including Hezbollah in Lebanon and Hamas in the Gaza Strip, where Israel remains at war.

President Donald Trump had been trying to dissuade Netanyahu from attacking Iranian nuclear sites, while U.S. and Iranian negotiators attempted to reach a deal to limit Iran’s nuclear activities.

U.S. and Iranian negotiators had been planning to meet Sunday in Oman for a sixth round of talks on a nuclear deal. But after the attack Friday, Iran announced that it would not participate in the talks Sunday.

Trump, in a social media post Friday, said Iran “must make a deal, before there is nothing left,” and he warned that the next round of Israeli airstrikes would be “even more brutal.”

U.S. officials said they were moving warships and other military assets in the Middle East to help protect Israel and U.S. troops in the region. The USS Thomas Hudner, a naval destroyer, was directed to sail to the Eastern Mediterranean, and a second destroyer may soon follow, the officials said. The Air Force will most likely move additional fighter aircraft to the region soon, an official said.

The military assets were not being positioned to take part in any offensive against Iran, a Pentagon official said. But they helped Israel shoot down Iranian missiles Friday, a U.S. official said, just as U.S. warships did when Iran fired a barrage against Israel in October.

Israel’s strikes Friday were the first time the country had openly attacked Iran’s nuclear sites, including its main nuclear enrichment facility at Natanz, which an Israeli military spokesperson said had suffered “significant damage.”

Social media footage verified by The New York Times shows flames and thick black smoke billowing from Natanz, shortly after explosions were reported there at 4:18 a.m. Satellite images reviewed by the Times showed several buildings and critical energy infrastructure there either destroyed or heavily damaged.

Rafael Grossi, head of the International Atomic Energy Agency, told the U.N. Security Council on Friday that Israel’s strike on Natanz had destroyed an aboveground enrichment plant, causing chemical and radiological contamination. Grossi said the leak was “manageable” with appropriate protection measures.

Netanyahu said he had ordered his security chiefs more than a half-year ago, in November, to destroy Iran’s nuclear program. The attack was originally planned for late April but was postponed for various reasons, he said, without elaborating.

“If Iran has a nuclear weapon, we simply won’t exist here,” he said in a videotaped statement Friday, adding that Israel was at the “12th hour.”

Israel’s allies expressed growing concern about the potential for the strikes to drive more conflict in the Middle East.

“Escalation serves no one in the region,” British Prime Minister Keir Starmer said, while the European Union’s chief diplomat, Kaja Kallas, called the situation “dangerous.” Egypt, which has a long-standing peace treaty with Israel, called the Israeli strikes “a direct threat to regional and international peace and security.”

Russian President Vladimir Putin condemned the Israeli strikes and offered to serve as a mediator in the conflict, the Kremlin said, even as Russia is conducting the largest bombing campaign of Ukrainian cities since invading that country three years ago.

Israel has been facing international condemnation over the past few months for escalating the war in Gaza after a ceasefire collapsed in March, and for holding back humanitarian aid as the population in the enclave edges closer to the brink of starvation.

Still, several important allies stood behind Israel on Friday. French President Emmanuel Macron said Israel had a “right to protect itself and ensure its security.” And Germany’s chancellor, Friedrich Merz, said Iran had refused to abide by agreements to limit its nuclear program and added that Tehran “poses a serious threat to the entire region, especially to the state of Israel.”