Two female College of Charleston students were assaulted in separate attacks late Tuesday, and police are asking for help in identifying suspects.

In the first incident, at about 11:20 p.m., a woman was walking north on Coming Street between Vanderhost and Calhoun streets when she was approached from behind by a man who demanded money, Charleston police public information officer Charles Francis said Wednesday.

When the woman told the man she didn't have any money, he sexually assaulted her, Francis said.

The assailant was described as a black male, 23 to 27 years old, 5 feet 9 inches to 5 feet 11 inches tall and 140 to 150 pounds. He had a dirty appearance, a scruffy beard, a shaved head and was wearing baggy jeans and a white zip-up jacket.

About 10 minutes later, a woman was walking on Radcliffe Street near King Street when a man grabbed her from behind, police said. She was able to fight off the attacker and got away. She was not sexually assaulted or injured.

The second victim described her assailant as a black male, 30 to 40 years old, 5 feet 5 inches to 5 feet 8 inches tall, with a scruffy beard and wearing a gray or tan hooded jacket and blue ball cap with white writing on it.

Both victims were walking alone when they were attacked, Francis said.

The college on Wednesday informed all students, staff and faculty of the attacks, said Mike Robertson, director of media relations.

"We're telling everyone to be aware of their surroundings and to be vigilant," Robertson said.

"We have expanded our patrols around the area, and we're working with city police to keep an eye on the area," he said.

Any student or staff member who feels uneasy about walking at night can contact the Public Safety Office for an escort, he said.