In an incident echoing a previous tragedy, an Iranian airliner maneuvered aggressively to avoid two F-15s over Syria. Though Israel was initially blamed, the US spoke right up, claiming the actions of the warplane were a standard inflight inspection.

Iranian Mahan Airlines Flight 1152  was near Damascus, Syria en route from Tehran to Beirut Lebanon on Thursday when it sighted two F-15s. The pilots used aggressive maneuvers to avoid the warplane, changing altitude. Data from the flight recorded by the website FlightRadar24.com showed the Iranian airliner climbed from 34,000 feet to 34,600 feet in under two minutes at the time of the incident, then dropped back down to 34,000 feet less than one minute later.

Iranian TV initially reported that two Israeli fighter jets came within a distance of 100 meters (328 feet) of the airliner. It was later reported on Iranian TV that the pilot of the Iranian plane stated the warp[lanes’ pilots had identified themselves as American over radio communication.

Several hours after the incident was reported on Iranian media, US Navy Capt. Bill Urban, a Central Command spokesman, told the AP that a US F-15 fighter jet “conducted a standard visual inspection of a Mahan Air passenger airliner at a safe distance of approximately 1,000 meters (3,280 feet) from the airliner this evening.”

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

“The visual inspection occurred to ensure the safety of coalition personnel at al-Tanf garrison,” Urban said. “Once the F-15 pilot identified the aircraft as a Mahan Air passenger plane, the F-15 safely opened distance from the aircraft.”

Three passengers and an unspecified number of crew members sustained injuries and were taken to hospital after the airliner landed in Beirut on Thursday evening.

Iran’s foreign ministry said that following the incident, a protest note was sent to the Swiss Embassy, which represents America’s interests in Iran, warning that if any accident happens on the plane’s return flight to Tehran, it will be the responsibility of the United States.

The ministry’s spokesman, Abbas Mousavi, said Iran is investigating the incident. The same note was also delivered to the UN Secretary-General António Guterres by Iran’s ambassador to the United Nations, Majid Takht-e Ravanchi.

“The explanations provided so far are unjustified and unconvincing,” Laya Joneydi, vice president for legal affairs, was quoted as saying by Iranian media.

“The harassment of a passenger plane on the territory of a third country is a clear violation of aviation security and freedom of civilian aircraft.”

Iran’s civilian aviation authority also was seeking to submit a formal protest to the International Civil Aviation Organization.

The incident raises harsh memories from 1988 when the US guided-missile cruiser,  USS Vincennes, inadvertently shot down Iran Air Flight 655 Airbus A300 en route from Tehran to Dubai, killing 290 people.

Mahan Airlines has been sanctioned by the US government since 2011  for allegedly shipping arms to Syria which also supply Hezbollah in Lebanon.