Israel has carried out a strike inside Iran, US official tells CNN, as region braces for further escalation

Israel has carried out a military strike inside Iran, a US official told CNN Friday, a potentially dangerous escalation in a fast widening Middle East conflict that Iranian government officials have so far sought to play down.

Iranā€™s air defense systems were activated in the cities of Isfahan and Tabriz after three explosions were heard close to a major military airbase near Isfahan, state media reported early Friday morning.

Maj. Gen. Abdolrahim Mousavi, the commander-in-chief of Iranā€™s army, said the explosions in the sky above Isfahan were related to anti-aircraft systems shooting at what he called a suspicious object, which did not cause any damage, Iranian state news IRNA reported. Other Iranian officials said air defenses intercepted three drones and there were no reports of a missile attack.

Iran has not identified the source of the strike.

The United States was given advance notification Thursday of an intended Israeli strike in the coming days, but did not endorse the response, a second senior US official said. Secretary of State Antony Blinken later confirmed the US ā€œhas not been involved in any offensive operations,ā€ but was focusing on Israelā€™s defense and de-escalation.

The US was ā€œinformed at the last minuteā€ about the attack on Iran, Italyā€™s foreign minister Antonio Tajani said at a news conference to conclude a meeting of the Group of Seven (G7) nations in Capri, Italy, which Blinken also attended.

Multiple state-aligned news agencies reported that sites associated with Iranā€™s nuclear program were secure and the attack appeared to be limited in scope.

Iranian media appeared to further minimize the scale of the attack on Friday, broadcasting calm scenes from Isfahan showing residents walking through parks and visiting landmarks. Traffic was reported as normal and the airport was also reported to have reopened after flights were briefly canceled or suspended early Friday.

Reports of Fridayā€™s strike came hours after Iranā€™s Foreign Minister Hossein Amir-Abdollahian told CNN that if Israel takes any further military action against Iran, its response would be ā€œimmediate and at a maximum level.ā€

ā€œIf the Israeli regime commits the grave error once again our response will be decisive, definitive and regretful for them,ā€ he added, noting that this warning had been communicated to the White House via the Swiss Embassy in Tehran.

Tensions across the Middle East remain on a knife edge, following Iranā€™s unprecedented direct strike against Israel late Saturday. The attack, during which Iran launched more than 300 drones and cruise missiles toward Israel, came in response to a suspected Israeli strike on an Iranian diplomatic complex in the Syrian capital, Damascus, on 1 April, which killed a top commander, and several others.

Separately, ā€œmaterial lossesā€ were reported in southern Syria after an Israeli strike, targeted ā€œour air defense sites in the southern region,ā€ Syrian state media SANA reported Friday citing a military source. The Israeli military said that it does not comment on reports in foreign media.

The Israeli military said it was unable to provide a comment on Friday, when asked by CNN about reports of explosions in Iran.

At the end of its three-day meeting in Capri, the G7 urged all parties in the region to ā€œprevent further escalation.ā€ Jordanā€™s Foreign Minister Ayman Safadi also warned the strikes risk ā€œdragging the region into further conflict,ā€ adding that the ā€œIsraeli-Iranian retaliations must end.ā€

Iran warned of ā€˜maximumā€™ response hours earlier

Israelā€™s action in Iran is the latest escalatory move in a region that has been rocked by Israelā€™s devastating war in Gaza following Hamasā€™ brutal October 7 attack. That attack killed more than 1,200 people, mostly civilians, and saw more than 200 others taken hostage.

Israelā€™s bombardment and siege of Gaza has killed more than 33,000 Palestinians, according to Palestinian officials, caused widespread destruction of the enclave and sparked a humanitarian crisis where more than 1 million people face ā€˜catastrophicā€™ levels of hunger.

Prior to Fridayā€™s Israeli strike, the US expectation was the country would not target Iranā€™s civilian or nuclear facilities, the senior US official told CNN.

CNN has previously reported that Israel told the US its response to the weekend attacks would be limited in scope. US intelligence had suggested Israel was weighing a narrow and limited strike inside Iran because they feel like they have to respond with a kinetic action of some kind given the unprecedented scale of the Iranian attack

The range of targets was ā€œnever specified in precise terms but nuclear and civilian locations were clearly not in that category,ā€ the senior official added.

Calls for restraint

Israelā€™s Western allies have both rallied to its defense in the wake of Iranā€™s attack Saturday, while also urging restraint.

US President Joe Biden told Israeli Prime Minister Benjamin Netanyahu he should consider Iranā€™s strikes a win, since they had been largely unsuccessful and demonstrated Israelā€™s ability to defend itself.

Biden had already made clear to Netanyahu that the US would not participate in any offensive operations against Iran in response, a senior administration previously told CNN.

Benny Gantz, a key member of Israelā€™s war cabinet, had pushed for a swift response to the attack, two Israeli officials told CNN, arguing that the longer Israeli delayed its response, the harder it would be to garner international support for it.

Some hardline officials have gone further. Israeli National Security Minister Itamar Ben Gvir said Israel should ā€œgo crazyā€ in response. Ben Gvir appeared to criticize Israelā€™s reported strike, publishing a one-word response on X early Friday morning ā€“ a slang word meaning ā€œlameā€ or ā€œweak.ā€

Israelā€™s opposition leader Yair Lapid called Ben Gvirā€™s comment ā€œunforgivable.ā€

ā€œNever before has a minister in the security cabinet done such heavy damage to the countryā€™s security, its image and its international status,ā€ Lapid said.

Jasmine El-Gamal, a former Middle East adviser to the US Defense Department, told CNN that Israel and Iranā€™s tit-for-tat strikes were about ā€œposturing and messaging.ā€

ā€œNeither side, obviously, is willing or ready to escalate into an all-out war. The Israelis in particular cannot get into an all-out war without the full support, both military and political, of the Americans, which President Biden made it clear he was not willing to give,ā€ she said.

El-Gamal said Israelā€™s reported strike was meant to tell Iran, ā€œWe can get to your nuclear sites if we want to. We know where they are, and even though we didnā€™t hit them this time ā€“ we can do it.ā€

This is a developing story and will be updated.

CNNā€™s Benjamin Brown, Irene Nasser, Christian Edwards, Nadeen Ebrahim, Jeremy Diamond and David Shortell contributed reporting.

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