Arizona State University has a problem: a serial groper's running amok on the university's Tempe campus.

Since March, the groper has assaulted at least six women, and police believe he may have struck again last night.

About 8:15 p.m. yesterday, a woman was walking by herself -- but amongst other people -- on the Tempe campus. She was approached by a man on a bike who sexually assaulted her and then rode off.

The victim, police say, got a good look at the guy and believes he is the same person responsible for the other attacks.

As we pointed out last week, the groper appears to be getting more brazen in his attacks -- making the jump from butt-grabs to boob-grabs and now assaulting woman while other people are around.

We spoke to ASU Chief of Police John Pickens last week, who said cops are working hard to track this guy down.

The suspect is described as a dark-haired male in his 20s.

Pickens says he encourages victims to report any incidents right away.

Anyone with information about ASU's serial groper is asked to call the ASU Police Department at 480-965-3456.