Two policemen have been charged with brutally beating a man, leaving him with broken bones and needing stitches, after his girlfriend found a video which showed they had savagely attacked him.

Najee Rivera was left covered in blood and with an eye swollen shut after police claimed they had been forced to restrain him after he slammed one into a wall when they pulled him over in North Philadelphia.

Officers had believed Kevin Robinson and Sean McKnight's version of events until Mr Rivera's girlfriend investigated the incident herself and found it was in fact the two police officers, rather than her boyfriend, who had been violent.

Najee Rivera was left bruised after he was beaten by two police officers who stopped him in Philadelphia and falsely claimed he had been violent, until Mr Rivera's girlfriend found a video proving police attacked him

Both have been charged with aggravated assault, conspiracy and related crimes.

The video, found by Mr Rivera's girlfriend Dina Scannapieco at a barber's shop, showed the two policemen punching and using batons to beat the 23-year-old, the Inquirer reported.

Police admitted the incident had not been investigated and the two officers had been believed without question. They may now review the way they deal with situations where someone arrested has been injured.

On May 29, 2013, Mr Rivera was pulled over by police for for running a stop sign on his scooter near Seventh and Cambria Streets in Fairhill.

Seeing the two officers armed with batons, he fled and they chased him.

On the 2700 block of North Sixth, a surveillance camera caught them knocking Rivera from his scooter, then grabbing and hitting him with fists and batons.

During the video Mr Rivera's screams can be heard.

The officers had claimed that Mr Rivera had fled after being stopped and then lost control of his bike, falling off in North Sixth. They then said he had slammed Robinson against a wall and attacked them 'with elbows.' He was then taken to Episcopal Hospital and the two officers' filed charges against him for assault and resisting arrest.

Kevin Robinson (left) and Sean McKnight (right) have been charged with aggravated assault and suspended

Mr Rivera was left needing stitches to his face and with a broken bone in his eye socket.

But when Miss Scannapieco went to the hospital and found her boyfriend beaten and covered in blood she did not believe the police's version and decided to turn detective herself.

She went back to the 2700 block of North Sixth and found her boyfriend's blood covering the pavement.

After asking around she managed to get hold of a surveillance video from a barber's shop which showed the brutal attack by the two officers.

They eventually handed themselves in and were suspended from duty and are likely to be dismissed.

District Attorney Seth Williams said: 'This type of behavior has absolutely no place in our city, and I will prosecute these two officers to the fullest extent of the law.'

In August 2013 all the charges against Mr Rivera were dropped.

Police Commissioner Charles Ramsey said before the video surfaced the officers' version of events had been accepted without question. He admitted the department should have investigated the area after the incident - a process which usually only takes place after an internal complaint is made.

He said McKnight and Robinson do not represent the majority of officers on the 6,500-strong force. But, he admitted, he could not guarantee all officers stick within the parameters of the law. He said: 'We've got to root them out.'

Mr Rivera said he has struggled to move on since the attack and had lost his job.

He added: 'Every time I get next to a cop or a cop is behind me, I get a little panic attack. And it's sad, because every cop ain't bad.'

Public Defender Bradley Bridge said his office is now to review arrests made in the past in light of the charges against the two officers.