A man drove up in front of a Dundee Drive house this morning, made eye contact with a teenage girl inside and masturbated while an interior light was on in his van, Ann Arbor police said.

Detectives are investigating whether the incident may be linked to a string of similar cases earlier this year in Dexter and Scio Township, police spokeswoman Lt. Renee Bush said.

No arrests have been made. According to police, the victim was working on a computer near a window at 12:45 a.m. when she saw a light on in a van parked in front of her home.

A man in the driver's seat took off his shirt and pants and began to masturbate, police said. One of the girl's parents called police.

The older model van was described as tan or light in color with a black stripe running down the side, police said. The driver was described as white, in his 40s, with thinning hair.

Anyone with information can call the department's tip line at (734) 794-6939.