Security procedures at MI5, Britain's domestic intelligence organisation, have been urgently reviewed and an inquiry has been launched after a laptop computer containing information about Northern Ireland was stolen from an MI5 officer at a London underground station, it emerged yesterday.
The £2,000 computer was stolen on March 4th when the officer put a case containing the computer on the floor between his feet after he was approached for help by youths at Paddington Station. The case was stolen and the MI5 officer and two police officers chased the thief but he disappeared down a corridor.
Downing Street sought to play down the seriousness of the security breach by describing the theft as "opportunistic" rather than the targeting of the MI5 officer.
"There are strict procedures for the moving of classified material," a spokesman said. "They have been tightened since this incident."
It is understood that the information contained on the computer does not relate to the peace process, terrorist suspects or possible bombing campaigns and is encrypted to one of the highest British government security levels. Security sources are "confident" the information will not be decoded.
A British government source was quoted yesterday as saying the computer contained information relating to the North but said there was no information about possible plans by the IRA or dissident republican groups to bomb Britain should the peace process fail.
However, the theft is highly embarrassing and a team of 150 MI5 officers and Special Branch detectives from Scotland Yard has been assigned to investigate the theft and track down the computer. A decision on whether the MI5 officer involved will face disciplinary procedures is also being considered.
The former Conservative Northern Secretary, Mr Tom King, who is chairman of the Parliamentary Intelligence and Security Committee, said he would be demanding a report from MI5 into the incident. "Any breach of security is serious and if you look back at our reports we have continually hammered the agencies . . . on the importance of security at all times."
Security experts were divided over whether the encryption could be broken. A former MI5 officer, Mr David Shayler, put the likelihood of a private individual breaking the code at "zero". However, spy writer Nigel West, also known as the former Conservative MP, Mr Rupert Allason, predicted it would only be a matter of time before the information was downloaded from the computer.