Tehran said its air defence system had shot down three drones overnight, triggering sirens.
It was initially unclear if the country came under attack, as no Iranian official directly acknowledged the possibility and Israel’s military did not respond to a request for comment.
Tensions have been high since the Saturday assault on Israel amid its war on Hamas in the Gaza Strip and its own strikes targeting Iran in Syria.
US officials declined to comment as of early Friday, but American broadcast networks quoting unnamed US officials said Israel carried out the attack.
The New York Times quoted anonymous Israeli officials claiming the assault, which came on Iranian Supreme Leader Ayatollah Ali Khamenei’s 85th birthday.
Iranian state broadcaster Mehr News downplayed reports of an attack, with a reporter in the city of Isfahan – where explosions were heard – had been unaffected.
He said: “The city is in complete calm and security, people are going on with their normal lives.”
“One, two hours ago, sounds were heard in the sky. We understand several miniature UAVs were overhead, which were shot down.”
Israel has yet to issue an official response to the reports but American media has claimed Joe Biden had previously warned Benjamin Netanyahu to avoid a strike.
