The Mahan Air plane was heading from Tehran to Beirut over Syrian airspace when US fighter jet passed by for what Washington called a routine inspection. The airliner landed safely in Beirut.

In this file photo taken on September 14, 2017, an Iranian airliner Mahan Air Airbus A340 aircraft is seen at the tarmac at Dubai International Airport.
In this file photo taken on September 14, 2017, an Iranian airliner Mahan Air Airbus A340 aircraft is seen at the tarmac at Dubai International Airport. (AFP)

Iran has threatened action against Washington after a US fighter jet intercepted an Iranian passenger plane in the skies over Syria.

Iranian officials said on Friday that one of their airliners, flying from Tehran to Beirut on Thursday, was “harassed” by fighter jets, but later landed safely in Lebanon. A US official confirmed a US jet had passed by the Iranian airliner, but at a safe distance.

Iran’s foreign minister, Mohammad Javad Zarif, said that what happened was an act of “lawlessness upon lawlessness.”

 “US illegally occupies the territory of another State and then harasses a scheduled civil airliner—endangering innocent civilian passengers—ostensibly to protect its occupation forces," he tweeted.

According to Iranian state TV, two fighter jets came within a distance of 100 metres (328 feet) of the Iranian Airbus A310.

The pilot of Mahan Air Flight 1152 quickly took the aircraft to a lower altitude to avoid a collision, the report said. The sharp manoeuvre caused slight injuries among some of the passengers.

However, US Navy Captain Bill Urban, a Central Command spokesman, said a US F-15 fighter jet “conducted a standard visual inspection” of the Iranian plane “at a safe distance of approximately 1,000 metres (3,280 feet) from the airliner."

He said the inspection was meant to ensure the safety of US coalition troops in al Tanf in Syria as the plane was flying over that area. He said once the aircraft was identified as a passenger plane, “the F-15 safely opened distance from the aircraft.”

Iran protested to the United Nations of a "flagrant violation" of international law after nearby US fighter jets sparked panic on an Iranian passenger plane over war-torn Syria.

The incident on Thursday was the latest between arch-foes Tehran and Washington since US President Donald Trump walked out in 2018 of a nuclear accord with Iran and renewed punishing sanctions.

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Under investigation

Aircraft at that altitude are to maintain a distance of at least 600 metres (2,000 feet) to ensure they don’t hit each other, though planes travelling that close can encounter wake turbulence.

The official IRIB news agency initially said a single Israeli jet had come near the plane but later quoted the pilot as saying there were two jets that identified themselves as American.

The pilot of the passenger plane contacted the jet pilots to warn them to keep a safe distance and they identified themselves as American, IRIB reported on Friday.

Video posted by the agency showed a single jet from the window of the plane and comments from a passenger who had blood on his face.

The incident is being investigated and Iran Foreign Ministry spokesman Abbas Mousavi said the necessary legal and political action would be taken, according to the Foreign Ministry website.

Accusations against Mahan Air

Israel and the United States have long accused Mahan Air of ferrying weapons for Iranian-linked guerrillas in Syria and elsewhere.

The United States imposed sanctions on Mahan Air in 2011, saying it provided financial and other support to Iran's elite Revolutionary Guards.

Tensions have spiked between Tehran and Washington since 2018, when US President Donald Trump exited Iran's 2015 nuclear deal with six powers and reimposed sanctions that have battered Iran's economy.

One passenger quoted in the IRIB report described how his head had hit the roof of the plane during the change in altitude and video showed an elderly passenger sprawled on the floor.

All of the passengers left the plane, some with minor injuries, the head of the Beirut airport told Reuters.

The plane arrived back in Tehran in the early hours of Friday morning, the Fars news agency reported. 

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Source: TRTWorld and agencies