Korean Air is to allow its staff to “readily” use tasers on unruly passengers after receiving criticism from US singer Richard Marx for the way it handled an on-board incident.

The airline announced tough new measures after Marx was forced to step in and help restrain a violent passenger during a flight from Hanoi, Vietnam, to Seoul in South Korea last week.

The singer later criticised Korean Air staff for “not knowing how to handle a situation like this without passenger interference” and said they were “clueless and ill-trained” to deal with the “psycho” passenger who had assaulted passengers and crew.

The airline has now announced new guidelines, including the use of stun guns “in a fast and efficient manner”. Previously crew members were only allowed to use the weapons in “grave” situations in which the life of a passenger or staff member was in danger.

The South Korean airline said staff would also undergo more comprehensive security training. Passengers with a history of violence will be banned from flying and at least one male crew member will be on board each flight.

In a statement it said: “We have decided to improve our conditions and procedure on using Taser guns to cope with violent acts and disturbances on board in a fast and efficient manner.”

A spokesman said regulations would be relaxed to allow crew members to “readily use stun guns”.

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The company’s president, Chi Chang-hoon, said Asian airlines had not followed US carriers in tackling on-board violence and suggested “Asian culture” was to blame. The number of illegal acts committed on planes in South Korea has trebled in the last five years, according to government statistics.

The passenger who was restrained by Marx has been charged with inflicting injury to the crew and a passenger during the flight. Korean Air said he had consumed two and a half shots of whiskey while on the plane.

Video of the incident posted on YouTube showed a young man in a business class seat spitting and swearing at crew members trying to restrain him with a rope.

Marx’s wife, Daisy Fuentes, said on Instagram that Korean Air staff “didn’t know how to use the taser and didn’t know how to secure the rope” around the unruly passenger.