Video footage captures the moment a man laughs as he pinned a police officer to the floor and threatened to slash her with a knife.

Gordon Finnlayson, 39, attacked the officer at a home in Northampton, on March 8, when officers attended following reports of an assault.

The video shows him walking down a hallway before he tells the police officers who have just arrived: ‘You are too late’.

He then slashes at one of the police officers who he pushed to the floor as she screams out in horror while Finnlayson laughs.

The other female police officer tried to disarm him but failed and both were repeatedly shoved and pushed to the ground.

One of the officers screams at him: ‘Put the knife down. Put the knife down.’ before he calls her a ‘bitch’ and runs out of the house.

Outside the house one of the police officers tearfully asks the other officer: ‘I don’t know if I’ve been stabbed.