Student Shot at Widener University

Campus is located about 15 miles southwest of Philadelphia.

Jan. 20, 2014— -- Police are searching for a gunman who shot a college student sitting in a car in the parking lot of Widener University's athletic center Monday.

The shooting happened at about 8:48 p.m. outside the Schwartz Athletic Center, a campus security official told ABC News. Campus security was notified after one of the on-campus blue phone "distress" buttons was pushed.

While police believe the shooter has left the campus, students were asked to stay indoors until 6 a.m.

University officials posted an alert about the shooting online, stating that the unnamed victim was taken to Crozer Chester Medical Center, and his family has been notified. Medical Center spokesman Grant Gegwich told ABC News that the victim was in surgery overnight, listed in stable but critical condition.

Chester police were reviewing surveillance footage and using K-9 units to track the suspect, who they believe fled into a residential neighborhood adjacent to the athletic complex, on the edge of the campus.

Police told reporters that they found one shell casing on the scene and believe the shooter used a revolver.

Widener is a private, co-ed university located in Chester, Pa., about 15 miles southwest of Philadelphia.

ABC News' Dan Good, Michael Howard and The Associated Press contributed to this report.