Israel has launched missiles against Iran in a retaliatory strike after being bombarded with rockets and drones last week, US officials said.
US intelligence officials said Israel had struck Iran directly in what would be major escalation.
Local sources suggested that an explosion occurred near an air force base that lies northeast of Isfahan, according to the Fars news agency, although authorities have not clarified what caused it.
“The cause of these sounds is still unknown, and investigations continue until the exact details of the incident are determined,” Fars news agency said.
White House and Pentagon officials are understood to be closely monitoring the situation as reports emerged late on Thursday evening.
No official confirmation of the attack has been released by either Israel, Iran or the US.
Iran has vowed to retaliate further if Israel strikes.
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