TEHRAN: Revolutionary Guard air marshals arrested a “counter-revolutionary” who tried to hijack an Iranian passenger plane headed for Syria, the Islamic republic's elite group said on Saturday.

Iran Air earlier said that Friday's foiled hijacking on its Tehran-Damascus flight 517 was the work of an unarmed “mentally unstable” man who had warned of a bomb on the plane.

“As the plane was approaching Damascus, one of the passengers falsely claimed he had a bomb and that the plane should land in another country,” an Iran Air spokesman told Mehr news agency.

“The air marshals immediately arrested the offender,” he said. They “talked to him, calmed him down and the plane safely landed in Damascus airport.”The unnamed man was handed over to authorities at Damascus airport, the airline said.

“The firm and timely intervention of security agents on the plane, members of the Revolutionary Guards, thwarted the attempt by an element linked to the counter-revolution,” the Guards, the regime's ideological army, said.

“This individual, whose identity is known and who is part of elements linked to counter-revolution, tried to hijack the plane by causing fear on the flight by pretending a bomb was on board,” it said in a statement on its website, Sepahnews.

Earlier Fars carried an unsourced report saying the incident happened on Saturday morning.

Iran's flagship carrier Iran Air has frequent flights to the Syrian capital, which many Iranians visit on pilgrimage. – AFP