Three US Marines are hailed as heroes for tackling a passenger and tying him to a seat after he barricaded himself inside a toilet 'screaming threats' during flight from Japan to Texas

Three hero US Marines on board a flight from Japan stepped in to detain a 'screaming' passenger by restraining him in a seat with cable ties. 

Captain Daniel Kult, Sergeant John Dietrick and Private First Class Alexander Meinhardt were headed to Texas from Tokyo on Monday when the incident took place.

A passenger on their flight barricaded himself in the restroom and began screaming, according to a statement from the Marine Corps. 

The screaming was so loud it alerted the marines to a potentially dangerous incident and the quick-thinking men sprung to action.

Dietrick, an infantry assault section leader from Mechanicsville, Virginia, said:  'While watching a movie during my flight from Japan to Texas, I started to hear screaming coming from the restroom on board. 

'When I took off my headphones, I heard a man sounding very distraught and screaming from the bathroom.' 

Daniel Kult (left) John Dietrick (centre), and Alexander Meinhardt (right) were described as 'men of action' after their heroic efforts to detain a screaming passenger

Dietrick alerted his colleagues to the disruption and the three marines waited outside the restroom while a flight attendant unlocked the door.

The men seized the unruly passenger before he could leave the restroom and cause further disruption. They restrained him for the rest of the flight by securing him in an onboard seat using cable ties. 

The plane was forced to divert to Los Angeles International Airport where the passenger was taken to hospital for a medical evaluation. 

'I knew I had to step in when he became a danger to others and himself,' said Meinhardt, a mortarman from Wisconsin. 

The hero marine said: 'I didn't think twice about helping restrain him through the rest of the flight.' 

Infantry officer Kult, from Iowa, said: 'We are well trained and it paid off today. 

'We just assessed the situation and acted. Working with the flight crew, we got the door open and from there worked together to subdue him. We didn't take time to talk it over. We just got ready and did what we needed to help.'  

The flight, which was headed to Tokyo, was force to divert to LAX Airport where the passenger was taken to hospital for medical evaluation (file photo of the Tom Bradley Terminal)

An LAX police spokesperson praised the marines' efforts and said they did a 'great job'. 

Their quick-thinking did not come as shock to colleagues, who heaped praise on the trio. 

'Honestly, I'm not surprised,' said Lieutenant Colonel Chris NiedziochaI.

'I happen to know all three of them, two of them well, and they are all what I would call 'men of action.' 

'I'm continually amazed by and grateful for the people we have in this battalion.' 

The marines were on their way back to the states from a Unit Deployment Program in Okinawa.  They had each been half-way through a six-month deployment when they were cleared for essential travel back to the US.

The onboard incident is now pending investigation by the US Attorney's Office for the Central District of California and LA's Federal Bureau of Investigation.