Israel struck military sites in Iran early on Saturday, but its retaliation for an Iranian attack this month did not appear aimed at the country's most sensitive oil and nuclear targets after urgent calls from allies and neighbours for restraint.

The risk of a wider conflagration between heavily armed Israel and Iran has convulsed a region already on fire with warfare in Gaza and Lebanon, but it was not clear whether the overnight strikes would trigger further escalation.

Israel’s military said scores of jets had completed three waves of strikes before dawn against missile factories and other sites, and warned its heavily armed arch-foe not to hit back.

Iran said its air defences had successfully countered the attack but two soldiers were killed and some locations suffered “limited damage.” A semi-official Iranian news agency vowed a “proportional reaction” to the Israeli strikes.

Tensions between Iran and Israel have grown rapidly since the October 7, 2023 attack on Israel by Iran-backed Hamas.

Fears of an escalation have increased since October 1 when Iran launched around 200 ballistic missiles at Israel, killing one person in the Israeli-occupied West Bank, in response to earlier Israeli moves and prompting new vows of retaliation.

Escalating conflict in Lebanon, where Israel is waging an intense campaign against Iran’s main regional ally Hezbollah to stop it firing rockets into northern Israel, has raised the temperature still further.

With the United States and many Middle Eastern countries urging restraint, all eyes are on Iran for how it will respond to Saturday's strikes.

Iranian news sites aired footage of passengers at Tehran’s Mehrabad Airport, seemingly meant to show there was little impact. Local media had reported blasts over several hours in the capital and at nearby military bases.

Israel's military, signalling it did not expect an immediate Iranian response, said there was no change to public safety restrictions across the country.

‘Obligated to Respond’

Israel’s military said it had struck truck missile manufacturing facilities and surface-to-air missile arrays, adding its planes had safely returned home.

“If the regime in Iran were to make the mistake of beginning a new round of escalation, we will be obligated to respond,” the military said.

Targets did not include energy infrastructure or Iran's nuclear facilities, a U.S. official said.

US President Joe Biden had warned that Washington, Israel's main backer and supplier of arms, would not support a strike on Tehran’s nuclear sites and had said Israel should consider alternatives to attacking Iran's oil fields.

Iranian authorities have repeatedly warned Israel against any attack.

“Iran reserves the right to respond to any aggression, and there is no doubt that Israel will face a proportional reaction for any action it takes,” the semi-official Tasnim news agency said on Saturday, citing sources.

A senior Biden official said Israel's “targeted and proportional strikes” should be the end of direct exchange of fire between the two countries, but the U.S. was fully prepared to once again defend Israel if Iran should choose to respond.

US Informed Ahead of Strikes

Videos carried by Iranian media showed air defences continuously firing at apparently incoming projectiles in central Tehran, without saying which sites were coming under attack.

Tasnim reported Islamic Revolutionary Guard Corps bases that were attacked were not damaged and said Iran was resuming flights from 9 am (0530 GMT) after a suspension during Israel’s attack. Neighbouring Iraq was also resuming flights, its state news agency said.

Israel launched air strikes against some military sites in Syria's central and southern parts early on Saturday, Syrian state news agency SANA reported. Israel has not confirmed striking Syria.

Israel said Prime Minister Benjamin Netanyahu, Defence Minister Yoav Gallant and other security officials closely followed the operation at the military's command and control centre in Tel Aviv.

Gallant spoke to US Defense Secretary Lloyd Austin shortly after Israel's strikes began. Austin emphasized the enhanced force posture of the United States to defend US personnel, Israel and its partners across the region, the Pentagon said.

Israel notified the United States before striking, but Washington was not involved in the operation, a US official told Reuters.

Saudi Arabia, which has mended fences with Iran after years of regional rivalry, and had been edging towards better ties with Israel before the war in Gaza, condemned the attack as a violation of Iranian sovereignty and international law.

Efforts to secure a ceasefire and hostage-release deal in Gaza, which could help cool the wider conflict, are expected to resume in Doha when negotiators fly there on Sunday. Months of talks have made little progress.