Iran's state media reported explosions in the central province of Isfahan Friday, as US media quoted officials saying Israel had carried out retaliatory strikes on its arch-rival.
Air defence systems over several Iranian cities were activated, state media reported, after the country's official broadcaster said explosions were heard near the city of Isfahan.
Israel had previously warned it would hit back after Iran fired hundreds of missiles and drones at Israel almost a week ago, in retaliation for a deadly strike -- which Tehran blamed on its foe -- that levelled Iran's consular annex at its embassy in Syria.
Fears of a major regional spillover from the Gaza war have since soared.
Iran's Fars news agency reported "three explosions" were heard near Qahjavarestan, near Isfahan airport and the 8th Shekari army airbase, while Iran's space agency spokesman Hossein Dalirian said "several" drones had been "successfully shot down".
Dalirian said on social media platform X there were "no reports of a missile attack".
"Reports indicate there was no major damage or large explosions caused by the impact of any air threat," the official IRNA news agency said.
The senior military officer in Isfahan, Brigadier General Siavash Mihandoost, told state television that the loud sound that people had heard was caused by defence systems shooting at a target in the air, not an explosion on the ground.
Nuclear facilities in Isfahan were reported to be "completely secure", Iran's Tasnim news agency said.
Washington received advance notice of Israel's reported strike, but did not endorse the operation or play any part in its execution, US media quoted officials as saying.
