CHICAGO (CBS) — Two teens remain hospitalized, as police look for the assailant who shot them as they waited for a bus near South Shore High School.

The shooting happened about 2:50 p.m. at 75th Street and Constance Avenue, according to police News Affairs Officer Daniel O’Brien. One victim was 17 and another was 18.

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Police say a gunman fired at a crowded bus stop outside the high school, at 7529 S. Constance Ave., then fled north down an alley.

Investigators say it’s possible the gunman could be identified by a police surveillance camera mounted just across the street. Also, a camera on the bus may yield some information.

Community activist Andrew Holmes says the offender needs to turn himself in.

“You know your days are numbered. There are cameras out here; may have your picture. Do yourself a favor. Turn yourself in,” he said.

A school spokeswoman said one of the victims was shot in the back. At least one of the wounded teens flagged down a westbound No. 75 bus after being shot. The driver stopped and called police, according to Chicago Transit Authority spokeswoman Catherine Hosinski.

CBS 2’s Mike Parker talked Monday with the mother of the other victim, who was shot in the leg. She said he was doing well, and that the young man’s friend, the other victim, had been shot twice.

One of the victims was taken to Northwestern Memorial Hospital, the other to Advocate Christ Medical Center.

The Sun-Times Media Wire contributed to this report.

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