A young woman was sexually assaulted in a Windsor schoolyard Tuesday night.

Police said the attack happened about 10:30 p.m. ET outside Queen Victoria School on Victoria Avenue.

The 21-year-old woman was cutting through the school property on her way home when an assailant pushed her in the back, causing her to fall.

The man held her down, cut her shirt with a folding knife and sexually assaulted her. He said he wouldn't hurt her if she kept quiet.

The man ran away and the victim went home and called police.

Police described the attacker as a black man, about 24 years old, between six feet and six feet two inches tall, weighing around 220 pounds with a pudgy, clean-shaven face.

Police said he was last seen wearing a black toque, gray Nike hooded sweatshirt and black gloves.