The crew of the Royal Navy's largest warship have marked their arrival in London by forming a huge set of Olympic rings on deck.

HMS Ocean, a carrier and assault ship, has returned to the capital to provide helicopter support and sniper teams for the duration of the Olympics.

As the huge vessel was towed by tugs through the Thames barrier, dozens of crew donned uniforms in the colours of the rings, before standing to attention in formation on deck.

The ship was already an integral part of the Government's Games security plans, however, its arrival in London coincided with the G4S scandal, which has seen thousands of troops bought in to replace security guards the contractor was unable to provide.