Edmonton Police say an 11-year-old girl was sexually assaulted in northwest Edmonton on Wednesday.

The girl was riding her bike in an alley in the Rosslyn neighbourhood around 12:30 p.m when she was stopped by a man.

She tried to get away but the man sexually assaulted her. The man fled when she started screaming for help.

Det. Mark Bourgeois commended the child for taking action when she got home.

"This child is very brave. Did all the right things. Told her parents right away and her parents reported to the police."

Police describe the suspect as a clean-shaven white male in his 40s with short dark hair and a deep voice.

The tall, slim man may have been wearing a dark jacket and running shoes at the time of the assault.