Inside secret building

News cameras have been allowed unprecedented access to a top secret Government spy agency as it announces eight in every 10 of the biggest British companies have suffered a serious cyber attack. 

The media was allowed to film in the secretive GCHQ in Cheltenham, which is home to one of the three UK Intelligence and Security Agencies, along with MI5 and MI6.

The visit comes after staff at the HQ, known as The Doughnut due to the shape of the building, were involved in the response to last week's terrorist attacks in Paris.

A GCHQ report was released yesterday revealing that serious cyber attacks cost the UK economy millions of pounds annually. 

The agency, along with MI5 and the Cabinet Office, has increased communication with private firms because the threat posed by cyber attacks has risen. 

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