SEATTLE -- Police have learned of a late-night attack near the campus of the University of Washington, but students have yet to be warned.

According to the police report, a man punched a 21-year-old student on an outdoor set of stairs last Saturday night, causing her to fall backwards. The man, whom the victim did not recognize, then jumped on top of her and groped her, scratching her chest and shoulders while doing so.

The victim was able to push the man off of her and run away. She was only able to provide a vague description of her attacker.

The stairs where the assault took place connect 21st Avenue Northeast to 22nd Avenue Northeast near Northeast 52nd Street.

Student Amy Monsen said she tries to avoid the stairs after dark, but sometimes get caught coming home late from class.

"I feel like it's very sheltered with trees and I have worried about it before," she said.

On Friday UW police said it has not yet issued an e-mail as it typically does whenever a crime is committed on or near campus because Seattle police is handling the case. Campus police said they have yet to be told any details of the attack, and they can't alert students until they do.

Seattle police said they typically share their findings with campus police. They said why such was not the case in this incident seems unclear, but said there is an effort under way to get the word out.

Earlier this week UW police announced plans to step up patrol with a hard-line approach to drunken rowdiness and other illegal behavior.