Princeton police are looking for a man who groped a 15-year-old girl Friday evening, and they believe the man could be a repeat offender.

They say the teen was walking in the area of Moore and Franklin streets when the suspect ran up from behind and grabbed her.

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He's said to have run off immediately afterward.

There have been eight similar assaults since 2015, all having taken place in a small area in central Princeton just east of downtown.

Based on the similarities between the assaults, police say they believe one man is responsible.

Police released a sketch of a suspect last year, along with surveillance video from one of the assaults.

Princeton Police Chief Nick Sutter says police have stepped up patrols in the area. Detectives are working aggressively to track down the suspect and take him off the street.

“Based on my training and experience, my fear would be that this is a person that you know is capable of escalating,” he says.

Anyone who lives in the area who has information or surveillance is being asked to contact police.