Police in charge of keeping the Olympics safe have lost the keys to Wembley Stadium.Scotland Yard admitted last night that it was to blame for the shocking breach.Search teams spent days desperately hunting for the keys after they were mislaid during the final preparations for the Games.Sources said it would cost up to ?40,000 to replace the hi-tech laser keys. The latest fiasco threatened to further damage already fragile confidence in security arrangements for the Games.It also provoked a furious behind-the-scenes row between the police, Locog and private security firm G4S over who was responsible.But late last night, Scotland Yard admitted a team of officers mislaid the ‘internal security keys’ during last minute checks.Claims that a set of keys were lost at the Wimbledon Championships in similar circumstances were flatly denied by tennis bosses and G4S.It is the latest blow to Olympic security after serious questions were raised about the ?284million Government contract with G4S to secure the Games. Military personnel were drafted in after the firm admitted it could not supply enough guards.More than ?600million has been spent securing Games venues, using more than 13,000 police officers from across Britain.