Firefighters broke into a high-security cockpit after an intruder locked himself inside a British Airways plane at Heathrow Airport.

The security scare was sparked on March 5 when the man slipped through the airport’s perimeter fence and boarded the empty BA 747 jet.

He then barricaded himself inside the bomb and bullet proof cockpit, designed to protect those flying the plane from acts of terrorism during a flight.

A source, who asked to remain anonymous, told the Mirror Online that it was a “terrifying situation”.

A source described the security lapse as "terrifying"

The source said: “It was a very difficult and complex situation and in the end the fire brigade had to be called to the plane and carried out a long and very protracted operation to get into the cockpit from outside.

“Eventually they managed to gain access to the cockpit and police were able to storm in and arrested the intruder.”

The drama unfolded at around 11.30am at the BA Engineering Base at Hatton Cross, where the plane was parked.

The source continued: “It is a terrifying situation when you think about it. Here is a man who not only has managed to go air-side at one of the world’s busiest airports but he has successfully got to a Boeing 747 jet liner and found it open and was able to climb aboard.

“Then he has got onto the flight deck and barricaded himself in using the plane’s own anti-terrorist equipment.

“As far as I know there is no suggestion he is in any way linked to terrorism but imagine if he had been a terrorist with the ability to handle the controls of a 747.

“Although it was away from the main runway, the plane could have caused a major incident and even worse, if it had taxied and taken off.”

Man due to appear in court

The Metropolitan Police said a man was due to appear in court on Monday (March 7) in connection with the incident.

In a statement it said: “Louis Pedro Verdasca dos Santos Costa, 38, of Stonehill Road, Hounslow , was charged on Saturday (March 5) with two counts: of unlawfully being airside, and unlawfully being on an aircraft.

“He will appear at Uxbridge Magistrates’ Court on Monday.”

A spokesperson for Heathrow Airport told getwestlondon said: “Safety and security are always our main priority and we take incidents involving either very seriously indeed. Individuals illegally entering the airside environment potentially endanger their own lives and those of others.

“We are working with the police following an incident on Saturday. We keep security under constant review.”