This is the moment a white American police officer punches a teenage black girl in the face after a dispute about how she and her friend crossed the road.

Video footage of Officer Ian Walsh lashing out at the 17-year-old in Seattle has shocked the U.S.

The confrontation began after Walsh spotted a man jaywalking - the American term for not crossing a road at a pedestrian crossing or junction controlled by lights - and went to speak to him.

According to the police report a group of four girls were also spotted doing the same and the officer called them over to his patrol car.

The women became verbally abusive and started to walk away ignoring the Walsh's instructions to remain where they stood.

When he tried to stop the teen two of them began grappling with him.

As the 17-year-old, wearing a pink top, tried to push away Walsh, he lashed out with his fist.

Other officers who had answered a call for help arrived on the scene and handcuffed the 19-year-old.

Both teens were charged with jaywalking and assaulting a police officer.

The case echoes the case of Rodney King, whose brutal beating by police prompted the Los Angeles race riots in 1992.

A police spokesman said they will review the video tape but said punching is a trained tactic for police officers.

'There will be a thorough investigation into this incident,' said a spokesman.

Both girls have now been released from custody