Police believed a woman was part of notorious Great Train Robbers gang

Detectives hunting the Great Train Robbers believed a woman was part of the notorious gang, secret documents have revealed.

Scotland Yard became convinced a “housekeeper” helped out at the villains’ countryside hideout where they counted the bundles of cash from the £2.6million heist on August 8, 1963.

Officers even tested pubic hair from sleeping bags at Leatherslade Farm in Buckinghamshire to try to identify her.

The revelations came in 50 pages of confidential Scotland Yard files obtained by the Mirror under the Freedom of Information Act.

A woman named Mary Manson was arrested by police who believed she had helped the gang, which included Ronnie Biggs and Bruce Reynolds. According to the accounts, “she was in danger of being ­implicated in the robbery itself because police were convinced a woman had been at the farm”.

The papers reveal Mary told officers after she was held: “I’m scared stiff about this.” The files said Mary came to the attention of police when she was spotted buying an Austin Healey sports car with Reynolds from a dealer in dealer in ­Chiswick, South West London.

He had hitchhiked to the capital to meet Mary and “treat himself” to a flash new motor. She handed herself in to police on August 21 after a picture of the car, which had been linked to the robbery, was flashed across TV screens ­nationwide – leaving her terrified.

A Flying Squad report said: “She knows a man called Bruce Reynolds and has been friendly with him for 10 years.

“She then tells of Reynolds asking her to buy an Austin Healey sports car in her name for him. She went with him to a car sales room at Chiswick and ­Reynolds gave her several bundles of five pound notes and told her to wait outside. Eventually, she went into the show room and Reynolds asked the salesman to make the sale to her.

“She gave her name as Manson, she has been known as McDonald for 16 years, and an address which was not her true address but one at which she had previously lived. She then signed forms and handed the salesman £835 in five pounds notes.

“She handed the ­documents relating to the car to Reynolds. She then left Reynolds who drove away in the Austin Healey car.”

Police found no incriminating evidence at Mary’s home and the pubic hair from the sleeping bag did not match hers. She was released on bail after six weeks. Mary was convicted of the much lesser offence of receiving the £835 stolen money.

But police remained convinced a woman was involved in the raid.

Reynolds, Biggs, Buster Edwards and several others were in the gang which held up a Royal Mail train heading from Glasgow to London in the early hours at Ledburn, Bucks. They tampered with signalling to bring the loco to a halt.

Driver Jack Mills was hit with an iron bar and suffered head injuries from which he never really recovered.

Most of the gang were eventually caught and jailed. Reynolds, Biggs and Edwards have since died.