CHICAGO (CBS) — A man tried to sexually assault a girl Wednesday night in the West Side Austin neighborhood, but was scared off when her cellphone rang.

About 7:40 p.m., the girl was walking home from school in the 5500 block of West West End Avenue when the man ran up to her, grabbed her, pulled her into an alley and threw her up against a wall, according to a community alert from Chicago Police.

The man held the victim against the wall and tried to unbuckle and remove her pants, but the girl’s cellphone rang and the man ran off, police said.

The suspect is described as a black man between 45 and 60, about 5-foot-7 and 170 pounds with dark skin and full beard, police said. He was wearing black cargo pants, gray zip-up hoodie and gym shoes.

Anyone with information is asked to call Area North detectives at (312) 744-8200.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)