AVONDALE — Police are warning CTA passengers after a girl was sexually assaulted by a man on a Blue Line train Thursday morning.

The girl, who police only identified as a juvenile, boarded the train at the Belmont station in Avondale just after 8 a.m. Thursday, according to a police-issued alert.

A man stood in front of the girl before inappropriately touching the girl’s body “on multiple occasions,” the alert said.

The girl then got off the train at the Division stop while the man stayed on the train.

The man is described as either white or Hispanic, between 20-29 years old, with facial hair across his chin and jaw line. He was wearing a baseball cap, a black jacket, black sweatpants and black and white Nike gym shoes.

Anyone with information is asked to call detectives at 312-744-8261. Anonymous tips can be submitted online.