BERKELEY -- A 25-year-old woman was sexually assaulted Monday night near People's Park and police need the public's help closing the case, authorities said.

UC Berkeley police said the woman was walking east in the 2600 block of Dwight Way at about 9:35 p.m. on Monday when a man yelled at her, ran across the street and grabbed her in the groin area. The man then ran west on Dwight Way toward People's Park, police said.

Authorities detained Roger Lopez, a 50-year-old sex offender, based on the victim's description, but released him without arrest after determining they did not have enough evidence to hold him. Police ordered Lopez -- who was not in compliance due to his failure to register as a sex offender -- to stay away from campus for seven days. Police say Lopez is a 50 years old, white, stands 5 feet 10 inches tall with a slim build, blue eyes and gray hair. Police said he was wearing a denim jacket, a black T-shirt, jeans and a green cap.

Anyone who witnessed the incident or who has information about the case is asked to call police at 510-642-0472 or 510-642-6760.

Follow Kristin J. Bender at Twitter.com/kjbender.



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