A British secret agent for the Serious Organised Crime Agency left information on dozens of informers and agents on a bus while working with Colombian customs.

Agent T had been moved from the SOCA station in Ecuador to Bogota, where she was to liaise with MI5, MI6, and the US Drug Enforcement Agency. She had downloaded "SOCA's crown jewels", including details of operations, code names and addresses of informers, onto a memory stick which she had in her handbag.

The stick contained five years of intelligence on the cocaine trade, as well as details of informants and agents. Agent T was recalled to London for an internal inquiry while those identified by the memory stick were moved to safety. A source put the cost of aborted missions at £100m.

A former colleague said of Agent T: "She’s a lovely girl but a bit daft and scatterbrained — the sort of person you could imagine forgetting her handbag on a bus.”

The failure is likely to add to criticism of SOCA, which is described by other agencies as "frankly amateurish”.

Although the incident happened in April 2006, Agent T has not been sacked and negotiations continue, according The Sunday Times.

SOCA said the screw-up happened while the agency was still being set up and that it now follows much stricter data guidelines.

The potential damage done by the lost data is much greater than an increase in spam or identity theft. Colombian cocaine cartels have a history of using technology to improve their trade and increase security.

The Cali cocaine cartel used to use an IBM AS/400 and bespoke data mining software to search for informants. The machine constantly checked the call log obtained from Colombian telecoms firms - it cross referenced all calls made against the home and office numbers of known DEA agents at the US embassy and Columbian police and investigators. This allowed the cartel to kill dozens of people and virtually destroy US drugs intelligence in the area. ®

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