Iran on Friday shot down three drones allegedly launched by Israel at a major air base and a nuclear site near the central city of Isfahan, reported Al Jazeera citing local media reports.

The action came hours after an unidentified official from the United States told CNN that Israel had carried out a military attack inside Iran. Another US official told the news channel that Washington did not endorse the strike.

Unidentified Israeli officials also confirmed to The New York Times that the country’s military had attacked Iran. This marks Israel’s first military response to Iran’s drone strike against it on Sunday.

Iran on Sunday had launched hundreds of drones and missiles toward Israel in its first-ever direct military attack on the country. The attack was ostensibly a response to a suspected Israeli airstrike on the Iranian embassy in Syria earlier this month that killed 16 people, including seven Islamic Revolutionary Guard Corps. The Islamic Revolutionary Guard Corps are part of the Iranian armed forces.

On Friday, Iran activated its air defence system after an explosion was heard near a major air base near the city of Isfahan, the Islamic Republic News Agency quoted Iranian officials as saying.

As a result, flights were suspended in several areas including the capital Tehran. The country’s airspace was reopened after nearly four-and-a-half hours, according to Al Jazeera. No casualties were reported.

Iranian Second Brigadier General Siavash Mihandoost also confirmed to the state news agency that no damage was reported due to the attack.

The facility at Isfahan is considered strategically important as it houses Iran’s fleet of F-14 Tomcats, an American-made fighter aircraft, according to AP. Three small Chinese-supplied research reactors are also operated from the facility, which handles fuel production and other activities for Iran’s civilian nuclear programme.

The nearby city of Natanz is one of Iran’s nuclear enrichment sites.

The International Atomic Energy Agency, the nuclear watchdog of the United Nations, said in a social media post later in the day that there was no damage to Iran’s nuclear site.

“Director General of the International Atomic Energy Agency Rafael Mariano Grossi continues to call for extreme restraint from everybody and reiterates that nuclear facilities should never be a target in military conflicts,” said the watchdog. “IAEA is monitoring the situation very closely.”

The strikes come amid increasing tensions in West Asia as Israel pushes ahead with its war on Gaza, which began over six months ago.

The Israeli military’s relentless air and ground operations in the besieged Palestinian territory have killed nearly 34,000 people so far. The war began after Palestinian militant group Hamas led an incursion into southern Israel on October 7, killing 1,200 people and taking over 200 hostages.