Anti-terror Osprey helicopters spotted flying over London landmarks

Anti-terror helicopters have been spotted flying over some of London's most famous landmarks.

The Osprey military helicopters, thought to belong to US forces, patrolled the skies over the capital. The unusual sight caused quite a stir on Twitter.

The high-tech aircraft is also known as 'The Transformer' because it can function as both a helicopter and fixed wing aircraft.

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