Shocking video has emerged of a police officer appearing to 'stamp on a man's head' after tasering him at an airport.

The video was filmed yesterday by a bystander at Manchester Airport - who said they "froze" when the witnessed the incident.

The traveller - who does not want to be named and who filmed the video - said: "I wanted police to stop but just froze - I was worried they were going to start shooting."

A spokesperson for Greater Manchester Police said: “Officers were called to reports of an altercation between members of the public in Terminal 2 at Manchester Airport.

“Whilst attempting to arrest one of the suspects of the earlier altercation, three officers were subject to a violent assault, where they were punched to the ground.

"A female officer suffered a broken nose and all three were taken to hospital for treatment.

"As the attending officers were firearms officers, there was a clear risk during this assault of their firearms being taken from them.

"Four men were arrested at the scene for affray and assault on emergency service workers.

"We acknowledge the concerns of the conduct within the video, and our Professional Standards Directorate are assessing this."