An Israeli missile has hit Iran, US officials have told the BBC’s partner station CBS News.
Blasts were heard in the central province of Isfahan and flights have been suspended over several cities, Iranian media say.
Iran is on high alert after Israel said it would respond to an Iranian attack against it on Saturday night.
Iran fired more than 300 drones and missiles in its first-ever direct attack on Israel.
Almost all were intercepted by Israeli air defences with support from the US, UK and other allies.
The Iranian attack was in retaliation for an Israeli strike which killed senior Iranian commanders in Syria on 1 April.
Isfahan province is home to a large air base, a major missile production complex and several nuclear sites.
