MADISON, Wis. -- Madison police are investigating three sexual assaults that have occurred in the last two weeks.

The latest incident occurred on Saturday morning when a female University of Wisconsin student was apparently abducted on the 500 block of North Carroll Street. She was taken to another location where she was sexually assaulted and then released, WISC-TV reported.

A similar incident occurred on Nov. 29 when an 18-year-old woman was abducted and sexually assaulted while walking on Observatory Drive.

Last Tuesday, a woman was violently assaulted in her own home on Jana Lane by an intruder, WISC-TV reported.

These incidents are raising concerns on the UW-Madison campus.

Tiffany Iliadis, a UW junior and Carol Street resident, said that she is concerned.

"I don't even want to go the library at 8 p.m., you know, it starts getting dark in the winter at 4 p.m. and I'm afraid to come home after dark," Iliadis said.

Emily Underwood, a UW freshman whose sorority is near the site of one of the assaults, said that she was taken off-guard by the attacks.

"It's weird (because) I've never felt unsafe on the campus yet," she said. "But now, there's so much happening in such a short time it's like, 'Oh my God, we need to do something about it.'"

Authorities said that they continue to investigate all three cases.