LONDON - Authorities say they have charged 11 protesters with impersonating police officers during demonstrations against the Group of 20 summit in London earlier this year.

The protesters were driving an armoured car around London's financial district when they were pulled over by police on the morning of April 1. Photos showed police swarming the vehicle as a man in blue overalls emerged from the turret.

The six-wheeled car was an Alvis Saracen, a model once used by the British army in Northern Ireland.

A protest group calling itself the Space Hijackers says it owns the vehicle and was behind the stunt.

The 11 protesters are due in court next month. City of London police said they are among 20 people charged over the protests.