AMHERST — A woman was attacked by an unknown assailant near the Southwest Residential Area early Thursday morning, according to a statement from the University of Massachusetts Police Department.

A stranger approached the woman from behind at around 2 a.m. in Lot 22, between Pierpont Hall and McGuirk Stadium, and punched her in the side of the head, police said. The attacker knocked the woman to the ground.

The incident, which was reported Thursday evening almost 17 hours after the assault, is under investigation by police. The victim was unable to provide police with a description of the person who assaulted her. Police are checking security cameras in the area, the statement said.

Anyone with information about this incident is encouraged to contact UMPD Officer Chris Stechmann at 413-545-2121. Anonymous information can be left at 413-577-TIPS (8477) or by using the UMPD anonymous witness form.

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