RAIL chiefs have launched an investigation after the exit door of a buffet carriage on a high-speed train burst open while it was racing through East Lothian, sparking panic among passengers and staff.

The incident happened on Monday morning as the Virgin East Coast service from Edinburgh to London was passing between Prestonpans and Longniddry.

The door, which should have been locked and secure, flew open, sending items from a catering trolley parked just inside it onto the track.

One of the passengers who was in the buffet car at the time that its door opened was Harry Barker, chairperson of East Lothian Community Rail Partnership.

He told the Courier that there was a loud bang followed by a scream from one of the catering crew as items were ‘sucked out’ of the open door.

Mr Barker said: “There was a terrific bang followed by a scream.

“The outside door in the buffet car had blown open at full speed but was still attached to the train.

“The train would or should not have been able to leave Waverley if the door had not been properly locked, but if it was some serious questions on safety now have to be asked by the Rail Accident Bureau. This should never have happened.

“The train was a 40-plus-year-old InterCity 125 with the manual doors which have to be opened from the inside to exit. Some years ago there were a number of incidents of people falling off these trains and being killed due to doors opening at speed without warning, which is why they have retrospectively had door locks fitted.”

Staff onboard the early-morning service hit the emergency stop button and the train halted on the track as the crew attempted to apply a temporary fix to the door.

Mr Barker said the train “limped on to Drem” before heading back to Waverley and terminating.

The train used on the service had manual doors which have to be opened from the inside to exit.

Historically referred to as ‘slam-door’ trains, most of these carriages have been phased out, although some InterCity 125 services still have them.

They are, though, supplemented with additional central driver locking which should not allow them to be opened until the train is stationary.

The cause of the door opening remains unknown; however, the Courier understands that the train had undergone a routine overnight maintenance check which would have involved doors being removed and then reattached.

One area of investigation may be whether there was a mistake when the door was put back on the carriage.

The Office of Rail and Road, which regulates the rail industry’s health and safety performance and investigates incidents, said it had been informed of the problem on the train.

A spokesperson said: “The Office of Rail and Road is aware of this incident and has started a preliminary investigation.”

A spokesperson for Virgin Trains on the east-coast route said: “We are currently investigating an incident on March 26 in which a train door became dislodged while the train was in service.

“No passengers or staff were injured in this incident and our staff responded by ensuring the train was brought to a standstill immediately.

“We have alerted the Rail Accident Investigation Branch about this incident and will cooperate fully with their investigations.”