(Bloomberg) -- Iran said a foreign security service and Kurdish groups were behind a drone attack on an Iranian ammunition depot last weekend which has escalated tensions in the energy-rich Persian Gulf.

Iran didn’t identify which country the security service belonged to, but has blamed regional enemy Israel for similar attacks in the past. The Wall Street Journal reported Sunday that Israel was responsible for the strike near the central city of Isfahan, citing unidentified US officials and people familiar with the operation.

The equipment and explosives were brought into Iran with the help of “Kurdish anti-revolutionary groups” in neighboring Iraqi Kurdistan under orders by the foreign security service, Iran’s state-run Nour News reported.

If confirmed as an Israeli operation, it would mark the first military attack conducted by Israel inside Iran since newly installed Prime Minister Benjamin Netanyahu last held office in 2021.

Gulf nations had been expecting an Israeli attack on Iran and see the strike as the start of renewed efforts to rein in the country’s nuclear and military ambitions, according to three people with knowledge of the issue from the region and a senior European diplomat in contact with Gulf governments.

The United Arab Emirates, which also has concerns about Iran and has ties with Israel that it established in 2020, is worried about the risks to stability of the Israeli actions, said the European diplomat and a fifth person in the region who’s familiar with the matter.

“These are pre-emptive efforts to deny Iran any advanced military capabilities,” said Riad Kahwagi, founder and CEO of INEGMA, a Dubai-based defense research group. “We should expect more.”

Iran has said three unmanned “suicide drones” targeted the Defense Ministry complex on Saturday. In the past Iran has retaliated for attacks by seizing ships in the region’s narrow shipping lane. Pointing the finger at Kurdish groups without naming the foreign country involved in the attack, though, may limit the response this time. 

Read more: Attack on Iran Raises Tension as Blinken Visits Israel PM

Iran has previously accused Kurdish groups in Iraq of instigating anti-government protests over the death of a Kurdish-Iranian woman, Mahsa Amini, in police custody in Tehran in September. 

Since the start of the unrest, Iran’s Islamic Revolutionary Guard Corps has launched several drone and missile attacks on what it calls “separatist terrorists” in northern Iraq. It’s framed these operations as retaliation for the protests or other attacks inside the country.

Israel has shifted its strategic doctrine from fighting Iran-backed groups like Hezbollah and Hamas on its own border to taking the fight directly to Tehran, former Israeli Prime Minister Naftali Bennett said at an event in New York on Wednesday.

Israel has the means and will to stop an Iranian nuclear bomb militarily, he said.

Israeli officials have declined to comment and the Pentagon denied US involvement. The State Department declined to comment on whether the US had prior knowledge of the strikes.

US Secretary of State Antony Blinken and Netanyahu said Monday that their countries are in agreement Iran must not have nuclear weapons and said they were working together to counter Tehran’s influence in the region. 

The Iran attack comes after warnings from the United States about Tehran’s military support for Russia and its invasion of Ukraine as well as aid in the opposite direction. 

In December, Washington said Russia was providing “unprecedented” military backing to Iran, possibly including air defense systems, warplanes and attack helicopters, in return for Iranian supplies of drones for the Kremlin’s invasion. An Iranian lawmaker last month said Tehran expects a delivery of Su-35 fighter jets from Russia by mid-March.

Saturday’s attack may have targeted a ballistic-missile factory, said Major General Amos Yadlin, former head of Israeli military intelligence. “This is not deciding a war with Iran, it’s another operation in a huge and long campaign to reduce the capabilities of Iran, military and nuclear, without escalating to full-scale war,” he told reporters.

--With assistance from Paul Wallace, Zainab Fattah, Fiona MacDonald and Gwen Ackerman.

(Adds former Israeli PM comment, other detail from 5th paragraph.)

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