After attempting suicide in March, a Paterson man called local authorities in search of help.

But what he received when he arrived at the hospital, federal authorities say, were brutal assaults at the hands of two city police officers who injured the man so badly he required surgery for one of his eyes.

After the victim insulted one of the cops from his hospital bed, the officer pulled on medical gloves and struck the man twice across his face, according to the FBI.

As his partner hit the cowering man -- warning him: "I ain't (expletive) playing with you" -- Officer Roger Then recorded video of himself smiling into the camera of his cellphone.

Investigators allege the officers never mentioned the attacks in their official report and concealed the cellphone video from law enforcement authorities.

Federal law enforcement finally caught up with Then on Wednesday, when the U.S. Attorney's Office says agents arrested the 29-year-old Paterson resident on a criminal complaint accusing him of conspiring to violate the man's civil rights and deliberately concealing the assault -- charges that could see him spend up to 10 years in federal prison if convicted.

Among the evidence cited by an FBI agent in the five-page complaint are the cellphone video in question and surveillance footage from the waiting area of the hospital's emergency room.

In the surveillance room video, the investigator wrote, Officer Then can be seen pushing the patient to the ground after the other officer -- who is not identified in the complaint -- punches the man as he sits in a wheelchair.

In their final report, investigators allege, the two officers wrote only that the victim, who they said had a history of psychiatric issues, "was restrained by officers and security staff" after he became combative and began to throw medical glove boxes at hospital staff.

Authorities have not detailed what led investigators to ultimately charge Then, whose arrest stemmed from a probe by the FBI, Passaic County Prosecutor's Office and the Paterson Police Department.

The U.S. Attorney's Office says Then is expected to make an initial appearance before a federal magistrate in Newark on Wednesday afternoon.

It's unclear whether the officer has retained an attorney who could comment on the charges against him.

Thomas Moriarty may be reached at tmoriarty@njadvancemedia.com. Follow him on Twitter at @ThomasDMoriarty.

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