Hamilton police are investigating after a 15-year-old Sherwood Secondary School student was allegedly grabbed and then punched in the face on the east Mountain Friday morning.

Police say the incident happened just after a 15-year-old student was getting off an HSR bus on Fennell Avenue near High Street around 8 a.m.

While walking to school, a man approached her from behind and grabbed her buttocks, police say.

"The female turned around and was punched in the face by the male who immediately ran off," a police news release reads.

The suspect is described as a white male, between 17 and 18-years-old, six feet tall with a heavy build and wearing dark clothing.

Anyone with information is asked to contact police at 905-546-3854.