A drone attack that caused a large explosion in the Iranian city of Isfahan was the work of Israel’s intelligence agency, Mossad, according to US officials.
In a daring operation, Israeli agents appear to have launched the attack from within Iran.
A US intelligence official said on Sunday that Israel was behind the attack but the Israeli military declined to comment.
Pentagon spokesperson Brigadier General Patrick Ryder confirmed no US forces had been involved but also declined to comment further.
But an Israeli intelligence expert says there are signs the strike was an Israeli operation.
Israeli intelligence analyst Ronen Bergman told Sky News: “The use of quadcopters is a very well-known stamp of Israeli intelligence and a source of concern for the Iranian regime because the short range of the drone means they were launched from inside Iran, highlighting Mossad’s capabilities.”
Mr Bergman is a pre-eminent authority on Mossad and author of Rise and Kill First, the Secret History of Israel’s Targeted Assassinations.
It is not clear how much damage was done by the drone attack.
Iran claims to have foiled the raid by shooting the drones down but Mr Bergman says Israel regards the operation to have been a success.
It has not been confirmed what was attacked, but footage shot by a witness in Isfahan shows a large blast at a military factory in the city.
The city is a centre of research and development for Iran’s missile technology.
‘Ukraine did warn you’
Israeli sources say the attack was unrelated to drone shipments to Russia.
Iran has been supplying Russia with cheap drones used to devastating effect on largely civilian targets in Ukraine.
Ukrainian government adviser Mykhailo Podolyak tweeted: “Explosive night in Iran, Ukraine did warn you.”
Iran has summoned Ukraine’s ambassador over the tweet.
Separately the Russian foreign ministry issued a statement condemning “any provocative actions potentially capable of provoking an uncontrolled escalation of tension in an already far from calm region”.
The attack is the first known use of force inside Iran to be carried out by Israel under its new far-right coalition government led by Benjamin Netanyahu.
But it suggests he is prepared to continue the hawkish policies of his predecessor Naftali Bennett who advocated a new “Octopus Doctrine” to deal with Iran.
Instead of striking at the Iranian regime’s many “tentacles” in the region, it advocates striking at its head.
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Mossad appears to have developed a significant presence inside Iran if it can carry out short range drone attacks on secret Iranian military sites with apparent impunity.
Israel has been reluctant to directly help Ukraine in a military sense, even though Russia is using weapons supplied by Israel’s enemies in Iran.
Israel does not want to alienate Russia and lose Russian permission to fly military sorties over Syria.
But this latest operation will please Kyiv if it has dented Iran’s missile capability.
Iran is thought to be considering supplying Russia with more advanced missiles than the drones it is currently sending.