Police responded to a report of sexual assault Saturday night at a Langdon Street apartment.
A 20-year-old woman called police when a man followed her into her apartment building on the 200 block of Langdon Street, according to a Madison Police Department incident report.
The incident occurred around 11:15 p.m. when the man made inappropriate sexual comments to the victim and proceeded to grab her butt, according to the report.
The suspect was still present in the area when police arrived, and was identified as 28-year-old Brandon Williams.
Williams was arrested for 4th degree sexual assault.