Chicago police are investigating a report of sexual assault at an off-campus fraternity house near the University of Chicago in Hyde Park. The reported incident occurred around 1:50 a.m. during a party at 5625 S. University Ave., according to a university alert issued Sunday. The woman, who is 21 and not affiliated with the university, told authorities she was assaulted by someone she did not know, the university said. The suspect ran away after another person intervened. Surveillance video captured someone matching the description running from the house, according to the alert. The university described the suspect as a South Asian man about 5 feet 7 inches tall, with short hair on the sides and longer, curly hair on top. He was reportedly wearing a black T-shirt, black jogging pants and white shoes. A University of Chicago police officer responded after being flagged down and arranged for the woman to be taken to the University of Chicago Medical Center. University police contacted the Chicago Police Department, which is leading the investigation. No one was in custody as of Monday. The address corresponds to the Alpha Epsilon Pi fraternity house. The fraternity said it learned of the allegation Sunday and that its University of Chicago chapter had suspended all events and programs while investigations proceed. It said the chapter was cooperating with university administrators and law enforcement. The university said fraternities are not recognized student organizations and have no formal affiliation with the school. It added that university students remain subject to its policies and disciplinary procedures, and that it would impose consequences if warranted. Anyone with information can submit an anonymous tip at CPDTIP.com. The university also lists sexual misconduct support and reporting resources at cares.uchicago.edu.