Police are looking for the suspect in a sexual assault Saturday in the West Pullman neighborhood on the Far South Side.

An 18-year-old woman was waiting for a CTA bus just before 2:30 a.m. when a man in a silver Chevrolet Impala pulled up next to her in the 11500 block of South Michigan Avenue and forced her into his car at knifepoint, according to Chicago Police.

He drove to the 11000 block of South Halsted, where he sexually assaulted her, police said.

The suspect was described as a black man between 30 and 33 years old, with short hair, a beard and a dark complexion. He was wearing a black T-shirt, black belt and a light-blue baseball cap, police said. The Chevy he was driving had front-end damage and was missing a front license plate.

Anyone with information about the incident is asked to call Area South detectives at (312) 747-8271.