Police are warning students at Sheridan College's Oakville campus not to walk alone and to avoid a nearby forested area if possible.
The warnings come after two women were sexually assaulted while walking on campus in the community west of Toronto.
One of the women was attacked near the college athletic building and the other on the trail system.
In both cases, the women were jumped from behind and when the victims screamed, the suspect fled.
He's described as a white male, about five feet seven inches tall.
Police say the suspect was wearing black clothing and had his face covered.