Footage of V-22 Osprey helicopters spotted flying over London, UK yesterday.

According to reports, the £50m heli-planes were in the capital to run an anti-terror training exercise.

The technololgically advanced aircraft can transport troops and deploy them on the ground where they're needed in record time.

Already used by the US Air Force, the British Army's Special Air Service were reportedly due to start operating Ospreys this year but it's not known if SAS personnel were on board.

This is a video of a couple V-22 Ospreys, worth £50 million each, showing off over London.

Based in RAF Mildenhall, the USAF were apparently running training flights to enable the SAS to respond to terror threats in London faster.