Hamilton police are asking the public for help in finding a sexual assault suspect.The assault happened near McMaster University at around 11:30 Thursday night. A woman in her 20’s was walking westbound on Sussex Street near Emerson Drive when a man grabbed her from behind and sexually assaulted her. Two witnesses heard her scream and chased the suspect as he fled west on Sussex, then South on Emerson. The victim suffered minor injuries.The suspect is described as an Asian man, in his late teens to early 20’s, about 5′ 6″ to 5′ 10″, clean shaven, with shaggy black hair and black framed glasses. He was wearing a white polo shirt with red stripes and light beige cargo pants. Anyone with any info is asked to call police.