University of Minnesota Police have issued a warning to students after a man sexually assaulted a woman Tuesday night on the East Bank, and in a separate case another man exposed himself to woman.

The incidents don't appear to be related, police said.

The first case occurred around 6 p.m. as a female student was walking west on Washington Avenue near the Moos Tower. A man approached from behind and grabbed the student in the genital area. The suspect the fled, police said.

He is described as a black male between 6 feet 3 inches and 6 feet 4 inches and of medium build. The suspect had scruffy facial hair and was wearing a black bulky jacket and a stocking cap at the time of the incident, police said.

About an hour later, a white man believed to be in his mid-40s approached a female student near the Science Classroom Building on Pleasant Street. He exposed himself to the student, then ran north on Pleasant Avenue, police said.

The suspect is between 5 feet 7 inches and 5 feet 11 inches. He was wearing round glasses, a navy blue jacket and a dark stocking cap when the incident happened at 7 p.m., police said.

Anybody with information is asked to call University police at 612-624-2677.