BERKELEY -- UC Berkeley police are investigating a sexual assault against a woman in People's Park late Sunday night, a lieutenant said Tuesday.

The attack happened between 10 p.m. and midnight in the park located off Telegraph Avenue and bordered by Dwight Way, and Haste and Bowditch streets, UC police Lt. Eric Tejada said. The woman, whose age was not given, is not a teacher, instructor or employee at the university, Tejada said.

Tejada said the suspect approached the woman from behind and displayed a gun before assaulting her in the park. The woman did not initially report the crime, Tejada said, instead waiting to do so until Monday.

The man police are looking for is of Filipino descent in his early 30s, Tejada said. He is approximately 5 feet, 8 inches tall and had a medium build with short black hair and dark-colored eyes, Tejada said.

Anyone with information on the assault is urged to call campus police at 510-642-6000.

Contact Rick Hurd at 925-945-4789 and follow at Twitter.com/3rdERH.