Two women say they were assaulted on the campus of Benedictine University earlier this month.
The 19-year-old women -- a student and her friend -- say they were attacked early on the morning of Sept. 15 inside their co-ed dorm after a night at a local bar.
A third friend called police after finding out what happened.
Six people of interest, all students, are being questioned by detectives with the Lisle Police Department.
A University police spokesman said the larger campus is not at risk because there's believed to be link between the victims and their attackers. But that hasn't stopped students from thinking about their safety.
"Whenever I have an opportunity, I try to walk with somebody else," a female student told NBC 5.
Police are asking anyone with more information about the attack to come forward.
School officials say if no charges are filed in the case, disciplinary action could still be taken against the students.