MINNEAPOLIS (AP) - Authorities say a University of Minnesota student was raped in her dorm room by two young men, one of whom was armed with a knife.

Campus police say the assault happened early Sunday morning in Sanford Hall. A campus alert sent Tuesday says the freshman was near her room when she "encountered two males who walked her back to her room." One threatened her with a knife once in the room, and both assaulted her.

The student told police she didn't know the men. No one has been arrested.

There have been six assaults on or near campus since February.

University spokesman Tim Busse says it's the first armed sexual assault of a student in a dorm that he can remember in his 15 years at the school.