Explosions could be heard in the Iranian capital, Tehran, though the Islamic Republic insisted they caused only "limited damage."
The attack risks pushing the archenemies closer to all-out war at a time of spiraling violence across the Middle East, where militant groups backed by Iran - including Hamas in Gaza and Hezbollah in Lebanon - are already at war with Israel.
Saturday marked the first time Israel's military has openly attacked Iran, which hasn't faced a sustained barrage of fire from a foreign enemy since its 1980s war with Iraq.
Israel's hourslong attack ended just before sunrise in Tehran, with the Israeli military saying it targeted "missile manufacturing facilities used to produce the missiles that Iran fired at the state of Israel over the last year." It also said it hit surface-to-air missile sites and "additional Iranian aerial capabilities."
Israel offered no initial damage assessment.
Initially, nuclear facilities and oil installations all had been seen as possible targets for Israel's response to Iran's Oct. 1 attack, but in mid-October the Biden administration won assurances from Israel that it would not hit such targets, which would be a more severe escalation.
"The regime in Iran and its proxies in the region have been relentlessly attacking Israel since Oct. 7, ... including direct attacks from Iranian soil," Israeli military spokesperson Rear Adm. Daniel Hagari said in a prerecorded video statement early Saturday. "Like every other sovereign country in the world, the state of Israel has the right and the duty to respond."
Iran's military said the strikes targeted military bases in Ilam, Khuzestan and Tehran provinces and caused "limited damage," without elaborating.
The United States warned against further retaliation, indicating that the overnight strikes should end the direct exchange of fire between the Israel and Iran.
Israel's military said explosions have been heard over northern Israel following its activity in southern Lebanon, but there "is no indication of a security incident."
Iran downplays Israel's attack
Iran's state-run media acknowledged blasts that could be heard in Tehran and said some of the sounds came from air defense systems around the city.
But beyond a brief reference, Iranian state television for hours offered no other details and even began showing what it described as live footage of men loading trucks at a vegetable market in Tehran in an apparent attempt to downplay the assault.
A Tehran resident told The Associated Press that at least seven explosions could be heard in the first wave of attacks, which rattled the surrounding area. The resident spoke on condition of anonymity for fear of reprisals.
As explosions sounded, people in Tehran could see what appeared to be tracer fire light up the sky. Other footage showed what appeared to be surface-to-air missiles being launched.
Iran closed the country's airspace early Saturday, and flight-tracking data analyzed by AP showed commercial airlines had broadly left the skies over Iran, and across Iraq, Syria and Lebanon.
Iran's move to quickly downplay the attack may offer an avenue for it not to respond, which could risk a further escalation.
"The Israel Defense Forces has fulfilled its mission," Hagari said in a later video. "If the regime in Iran were to make the mistake of beginning a new round of escalation, we will be obligated to respond."
Israel's assault was a response to Iranian attacks
Iran fired a wave of missiles and drones at Israel in April after two Iranian generals were killed in an apparent Israeli airstrike in Syria on an Iranian diplomatic post. The missiles and drones caused minimum damage, and Israel - under pressure from Western countries to show restraint - responded with a limited strike it didn't openly claim.
Iran launched at least 180 missiles into Israel on the evening of Oct. 1, sending Israelis scrambling into bomb shelters but causing only minimal damage and a few injuries. Iran said the barrage was retaliation for attacks in recent months that killed leaders of Hezbollah, Hamas and the Iranian military. Israeli Prime Minister Benjamin Netanyahu immediately said Iran had "made a big mistake."
Before Iran's October attack, Israel had landed a series of devastating blows against Hezbollah, which has been firing rockets into Israel near-daily for over a year - ever since the deadly Hamas attack against Israel that sparked the war in Gaza.
Dozens were killed and thousands wounded in September when pagers and walkie-talkies used by Hezbollah exploded in two days of attacks attributed to Israel. A massive Israel airstrike the following week outside Beirut killed Hezbollah's longtime leader, Hassan Nasrallah, and several of his top commanders.
Israel then ratcheted up the pressure on Hezbollah by launching a ground invasion into southern Lebanon. More than a million Lebanese people have been displaced, and the death toll has risen sharply as airstrikes hit in and around Beirut.
Israel has said it will continue to strike Hezbollah until it is safe for Israeli citizens displaced from their homes near the Lebanon border to return. Hezbollah has vowed to keep firing rockets into Israel until there is a cease-fire in Gaza.
The US warns against retaliation
The White House indicated that Israel's strikes on Iran should end the direct exchange of fire between the two enemy countries, while warning Tehran of "consequences" should it respond.
A senior White House official said the administration believed the Israeli operation should "close out" the direct military exchange between Israel and Iran, and said other allies were in agreement.
United States President Joe Biden was updated throughout Israel's operation, the official said, while underscoring that the U.S. had no involvement in the attack.
The official, who briefed reporters on the condition of anonymity under ground rules set by the White House, said the Israeli operation "was extensive, it was targeted, it was precise."
U.S. Defense Secretary Lloyd Austin spoke with his Israeli counterpart, Yoav Gallant, about Israel's strikes on military targets in Iran, Maj. Gen. Pat Ryder said late Friday.
Austin reiterated that the U.S. was committed to its ally's security and that Israel has a right to defend itself, though Washington was determined to prevent the conflict from expanding, the Pentagon press secretary said in a statement.
Israel's strike is the latest in the Mideast wars
When Hamas and other militants attacked Israel on Oct. 7, 2023, they killed 1,200 people, mostly civilians, and took some 250 hostages into Gaza. In response, Israel launched a devastating air and ground offensive against Hamas, and Netanyahu has vowed to keep fighting until all of the hostages are freed. Some 100 remain and roughly a third are believed to be dead.
More than 42,000 Palestinians have been killed in Gaza, according to local health officials, who don't delineate between civilians and combatants but say more than half of the dead are women and children.
Israel and Iran have been bitter foes since the 1979 Islamic Revolution. Israel considers Iran to be its greatest threat, citing its leaders' calls for Israel's destruction, their support for anti-Israel militant groups and the country's nuclear program.
During their yearslong shadow war, a suspected Israeli assassination campaign has killed top Iranian nuclear scientists and Iranian nuclear installations have been hacked or sabotaged, all in mysterious attacks blamed on Israel.
Meanwhile, Iran has been blamed for a series of attacks on shipping in the Middle East in recent years, which later grew into the attacks by Yemen's Houthi rebels on shipping through the Red Sea corridor.
Since Hamas' Oct. 7 attack, the shadow war has increasingly moved into the light.
___
Associated Press writers Amir Vahdat in Tehran, Iran; Tia Goldenberg in Tel Aviv, Israel; Abby Sewell in Beirut; and Lolita C. Baldor, Farnoush Amiri and Zeke Miller in Washington; and Aamer Madhani in Wilmington, Delaware, contributed to this report.