Police Officer Threatens Citizen With Anal Rape

WA Police have confirmed they are investigating a video showing a heated confrontation between a traffic officer and a member of the public which has gone viral on Facebook.

The 45-second video shows an officer responding aggressively to comments made by the member of the public filming the incident.

The man was stopped by the first-class constable for riding a bike without a helmet in Forrestfield about 2.30pm on Tuesday.

At a press conference in Perth on Wednesday morning police confirmed they were investigating a video posted on Facebook by 'John Gds Martin' and that the constable had been spoken to by his direct supervisor.

The video, shared through the Facebook page "50 shades of straya", has been liked more than 15,000 times, shared more than 500 times and has received more than 4000 comments in the 14 hours since it was posted.

Inspector Dom Wood said the officer could have dealt with the situation in a more appropriate manner.