ADELPHI, Md. — Authorities say a security guard has been shot near a university conference center in Maryland during a robbery.

Campus police Chief David Mitchell said at a news conference that officers called to the University of Maryland University College’s Inn and Conference Center early Tuesday for a report of the shooting found the injured guard. Mitchell says he’s in critical condition.

Mitchell says two armed men stole three safes, which were found nearby. He says one man was arrested, but they’re searching for the second.

According to its website, the school offers online courses and enrolls about 80,000 students around the world, including active duty military personnel. Its headquarters and conference center in the Washington, D.C., suburbs are next to the University of Maryland, College Park campus.