ANN ARBOR, MI (WDIV/CNN) - The FBI is joining a police investigation into a string of sexual assaults around the University of Michigan campus, where more than 6 incidents have been reported.
Police have released two sketches of a possible perpetrator because victims have given differing descriptions of their attackers. One is a white male, with brown hair and eyes, and the other is a man with dark hair, dark eyes and a tan, or olive complexion.
Authorities said they're not ruling anything out at this point, but one thing is clear - the attacker or attackers isn't backing off.
The latest attack happened Tuesday in the 700 block of State Street. A female student was grabbed around 11:30 at night and fondled, but managed to get away.
The tally now stands at two raped, one sexually assaulted, and three others attacked that escaped.
Police are on the streets and have called in the feds for help, but have warned women living in the area to not walk alone at night - period.
"At this point, I don't think anyone's walking alone at night," student Joanna Smulska said. "The problem's gotten out of hand. Like we all stick together and I hope nothing else happens."
A reward is being offered for any information leading to an arrest.
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