PHILADELPHIA (CBS/AP) — Police say four people, including an off-duty police detective and his wife, were injured in a “flash mob” attack by some teens among a crowd of juveniles in Center City Philadelphia.

Police say a large crowd of juveniles were at 16th and Walnut Streets at about 6 p.m. Saturday when some among the group began randomly assaulting people on the street. The 55-year-old detective was punched from behind when he tried to make arrests and was left with an orbital fracture to his right eye. His 53-year-old wife was also punched in the face after she tried to come to husband’s aid.

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The couple and two other victims were taken to Jefferson Hospital for treatment. Two others declined medical attention.

Two 16-year-old youths were arrested after another attack nearby.

Police are seeking surveillance video to try to identify other suspects and asking anyone with information to come forward.

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