A late-night Malaysia Airlines flight was turned back to Melbourne Airport shortly after take-off following a security incident involving a "disruptive" and "threatening" passenger who tried to enter the plane's cockpit while carrying an unidentified black object, the airline and local police say.
One fellow passenger described seeing the man behaving erratically and threatening to "blow the plane up" before he was eventually pinned to the floor and subdued by others on the plane. A Malaysian government official later told local media the man had been holding a power bank, or mobile charger, not an explosive device.
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A man was pinned by passengers and arrested by armed police on Malaysian-bound flight MH128.
Dramatic photographs taken by other passengers on board the flight showed heavily armed security personnel boarding the plane after its return to Melbourne. The aircraft landed safely about 30 minutes after take-off and the passenger was apprehended by airport security.
Flight MH128, which left Melbourne for Kuala Lumpur at 11.11pm, was turned back "after the operating captain was alerted by a cabin crew of a passenger attempting to enter the cockpit", the airline said in a statement.
In air traffic control audio posted online, a male voice can be heard saying: "We have a passenger trying to enter the cockpit."
About three minutes later, the same male voice can be heard saying the passenger was "claiming to have an explosive device, tried to enter the cockpit, has been overpowered by passengers".
"However, we'd like to land and have the device checked," the voice says.
Victoria Police, who are investigating, said in a statement the man had allegedly threatened the safety of passengers and staff before being subdued.
Former AFL player Andrew Leoncelli was sitting in business class, several seats away from the cockpit, when the incident unfolded. He described seeing a man carrying a large black cylindrical object which looked like speaker, which appeared to have an on/off button and a charging port.
Mr Leoncelli said the passenger was "screaming" at a flight attendant, saying, "I need to see the captain" and walking to the front of the aircraft during take-off.
Mr Leoncelli said the passenger said: "I've got a bomb and I'm going to f---ing blow the plane up."
The flight attendant yelled at the man to sit down and, when he refused, she called out for help.
Mr Leoncelli said at this point he unbuckled his seatbelt and went to confront the man who he said appeared agitated and kept repeating his threat.
"Literally he was eyeball-to-eyeball with me, saying he was going to blow the plane up.
"He looked like a lunatic," he said.
"For some reason he lost his nerve and he ran ... and he headed towards the back of the plane.
"I hadn't done anything to him except confront him," he said.
Mr Leoncelli then said others on the plane were able to overpower the man.
Two young Australian men who were passengers "went to work on him and got him in the shackles good and proper, they were the heroes", Mr Leoncelli said. A picture taken by another passenger and posted to Twitter showed a man lying flat on his stomach on the floor of the plane with his hands bound behind his back with plastic handcuffs.
#MH128 guy drunk. In plastic cuffs. Looks like the SWAT team was despatched to the flight @MAS pic.twitter.com/FL5TqTEGR3
— saroki (@saroki19) May 31, 2017
Malaysia's Deputy Transport Minister Abdul Aziz Kaprawi was quoted in The Star, a local news outlet, saying the passenger was drunk and that the object he was holding was a "power bank", not an explosive device.
When the plane landed, passengers were left on the tarmac for about 90 minutes, with very little information from airline staff about what was happening, Mr Leoncelli said.
Eventually, heavily armed security staff wearing camouflage uniforms and helmets entered the plane and removed the man.
As he waited on the plane, Mr Leoncelli recorded a video.
"There's a giant black object on this plane, a crazy guy wants to blow it up, who was subdued," he said.
"The police are sitting four kilometres away, haven't moved in 25 minutes. This is an absolute joke. Seriously, help us."
During the lengthy wait on the tarmac, others took to Instagram to express their frustration and fear.
"We have been waiting in the plane for an hour, still waiting for the police," one passenger wrote. "The bomb may go off any time."
MH128 landed safely at Melbourne Airport at 11.41pm, the company said.
"Following the incident on MH128, the disruptive passenger has been apprehended by airport security. Malaysia Airlines together with the Australian authorities will be investigating the incident," the airline said.
Malaysia Airlines stressed that "at no point was the aircraft 'hijacked' ".
Flights to Melbourne Airport were diverted immediately after the incident, according to the 24-hour aviation monitoring website Flight Radar.
Victoria Police said there was "no imminent threat to passengers, staff or public and the investigation is ongoing".