A Jewish popstar has stepped in to help flight attendants after a passenger on his Korean Air Flight became aggressive towards other passengers and crew. 

Richard Marx, whose hits include Endless Summer Nights, Right Here Waiting, and Now and Forever, was travelling from Hanoi in Vietnam to Seoul in South Korea, on Korean flight 480,  when the unruly passenger allegedly began attacking others on board.

He tweeted: "You will be hearing about our flight#480 on @KoreanAir_KE . Passenger next to us attacked passengers and crew." And added that the "entire chaotic and dangerous event" lasted four hours.

Mr Marx later added on Facebook: "My wife and I are safe but one crew member and two passengers were injured.

"The all female crew was clueless and not trained as to how to restrain this psycho and he was only initially subdued when I and a couple other male passengers intervened. 

"He then later easily broke his restraints and attacked more crew and another passenger. When we landed in Seoul police boarded the plane.

"Heading home to Los Angeles soon but Korean Air should be sanctioned for not knowing how to handle a situation like this without passenger interference."

Mr Marx's wife, Daisy Fuentes, later wrote on her Facebook page: "On our flight from Hanoi to Seoul a guy sitting in the next row from us got crazy & started attacking the flight attendants & passengers.

"When he started pushing the female staff and pulling them by the hair Richard was the first to help subdue him.

"This went on for FOUR hrs. I feel horrible for the abuse the staff had to endure but no one was prepared for this.

"They never fully got control of him. They didn't know how to use the taser & they didn't know how to secure the rope around him (he got loose from their rope restraints 3 times)."

One of the pictures on Ms Fuentes's Facebook page shows an air stewardess pointing a Taser while another shows a man with ropes wrapped around his arms and shoulders, apparently strapped to his chair.

Korean Air told Business Insider in a statement: "According to the response protocol, Korean Air's flight attendants have subdued the unruly passenger and tied him up with ropes."