Staff at Britain’s major signal listening and intercepting station ‘lost’ 35 laptop computers in the course of a year, a parliamentary committee has been told.

The computers went missing when staff at GCHQ took them off-site to carry out work. In three cases, the machines were certified to contain top secret information.

In their report, the committee said it appeared that logging of the whereabouts of the computers at the time of the incidents, in 2008, had been “haphazard”, Reuters reported.

The security lapses demonstrated a “cavalier” attitude to the security and tracking the whereabouts of the computers, the committee said.

GCHQ operates on a similar basis to the United States’ National Security Agency, and reports to the foreign minister. Its main work is to intercept and translate communications.

“The Committee considers that this formerly cavalier attitude towards valuable and sensitive assets was unacceptable. GCHQ must ensure that it controls, tracks and monitors its equipment effectively. Now that proper processes have been introduced, we trust that this problem will not arise again,” the report’s conclusion said.

In response, a government statement said it accepted the committee’s criticism and conceded that GCHQ had been unable to account fully for all of its laptops at that time.

“However, GCHQ has no evidence of any loss of laptops or classified information,” it said. “The most likely explanation in most cases is that the laptops were destroyed but without the destruction being fully recorded. GCHQ has now tightened up its controls.”

The government has been repeatedly embarrassed by lapses over missing laptops and storage devices involving losses of information, such as when tax authorities lost data on 25 million people exposing them to the risk of identity theft and fraud.