By Natasha Brown

PHILADELPHIA (CBS) — Two brothers — one a Philadelphia Police inspector and the other a former detective — are facing charges. The charges stem from the assault of a man with Asperger syndrome, a form of autism.

The incident took place last August.

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Insp. James Smith and former Detective Patrick Smith are facing criminal charges for their alleged role in the vehicular pursuit and assault of a 27-year-old man with Asperger syndrome.

The district attorney says shortly after midnight on Aug. 19, the victim, who was on foot, was chased by the two off-duty officers in a car into a shopping center at Fairdale Road and Knights Road in Northeast Philadelphia.

Both officers are alleged to have identified themselves as town watch before the incident allegedly turned violent.

“They are further alleged to have chased the victim on foot, grabbed him, pushed and slammed him into a wall and forced him to the ground. This activity caused a black eye and abrasions on the back of the victim’s head, elbows and knees, in addition to the obvious distress,” Philadelphia District Attorney Larry Krasner said.

The 27-year-old man had called his mother just before the scuffle.

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“The complainant, out of breath from running, called his mother. The complainant’s mother heard a voice say, ‘Hold his legs,” Krasner said.

Investigators say the officers began the chase thinking that the man was involved in car break-ins, but the police internal affairs division later concluded that was not the case.

Detective Smith retired from the department in September. Insp. Smith and the former detective were both arrested on Thursday.

Fraternal Order of Police President John McNesby gave a scathing rebuke of the DA’s charges against the two veteran officers, saying the charges are unwarranted.

“Both of these officers, misdemeanor charges over something like this when we’re losing a record number of children on the street, a record number of people dying in shootings and this is what he’s concerned about,” McNesby said.

“Obviously it’s very disturbing that anyone, in this case two fairly high-ranking police personnel, believes it’s OK to act as vigilantes,” Krasner said.

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Patrick Smith, the brother who formerly worked for the police department, is now an agent for the Philadelphia Gun Violence Task Force. He’s been placed on administrative duty.