US intelligence in recent days received indications that Iran has put sections of its air defense system on high alert, according to a Thursday report.
A US official told CNN that there were “several” indications of the development, without specifying what the intelligence was based on.
The raised alert level is not related to training, but to recent events and fears of threats, the report said.
A series of mysterious fires and blasts have rocked Iran in recent weeks. Several of the recent disasters have struck sensitive Iranian sites, leading to speculation that they could be part of a sabotage campaign engineered by Israel.
The blasts included an explosion on July 2 that damaged Iran’s Natanz nuclear facility and, a week before that, a large blast felt in Tehran, apparently caused by an explosion at the Parchin military complex, which defense analysts believe holds an underground tunnel system and missile production facilities.
Despite Iran putting its air defenses on high alert, apparently in response to the recent incidents, none of them appear to be linked to air strikes.
A Middle Eastern intelligence official was quoted earlier this month by The New York Times as saying the fire that badly damaged a building used for producing centrifuges at Natanz was sparked by Israel and was caused by a powerful bomb.
But the unidentified official said Israel was not linked to several other recent mysterious fires in Iran over the past several weeks.
Iran last week called for action against Israel following the damage to the Natanz facility, and appeared to acknowledge the fire there was not an accident.
Israeli TV reports, without naming sources, have said the Natanz blast destroyed the laboratory in which Iran developed faster centrifuges and set back the Iranian nuclear program by one or two years.
A Thursday report said that two cyber attacks hit Israeli water infrastructure in recent weeks, without causing damage. Officials did not say who carried out the attacks on the pump stations. Iran allegedly attacked Israel’s drinking water in a cyber attack in April.
Israel was reported to have been behind a cyber attack in May on an Iranian port facility, causing widespread chaos, apparently in retaliation for the attempt to target Israel’s water infrastructure.
Iran’s Revolutionary Guard in January mistakenly shot down a Ukrainian jetliner outside Tehran, killing all 176 people aboard.