An Israeli long-distance aircraft fired missiles at Iranian Air Force assets in Iran's central Isfahan province, The Jerusalem Post newspaper said.
The daily, however, did not provide a source for the allegation.
Iranian state media reported early Friday that air defenses were activated against suspicious objects in several cities, including Isfahan, amid reports of an alleged Israeli attack.
The semi-official Mehr News Agency said three drones were destroyed in the skies above Isfahan.
Iran's state television confirmed "massive explosions" in Isfahan, but said no nuclear facilities were affected or targeted in the central city.
US media reports, citing officials, said that Israel had carried a strike inside Iran.
There was no official Israeli comment yet on reports of launching attacks inside Iran.
Tension escalated between Iran and Israel after Tehran launched a drone and missile attack on Saturday in response to the April 1 attack on its consulate in Syria, in which seven military advisers were killed.
Israel, which has not formally taken responsibility for the consulate attack, has vowed a military response to Iran's weekend attack.
Israel is the only Middle East country that has F-35 aircraft capable of reaching Iran while avoiding radar detection.
Israeli officials have previously hinted in recent years at the possibility of using this type of aircraft in attacks against Iran.
