The Katzen Arts Center on the campus of American University in Washington, DC. (Photo by Jahi Chikwendiu/Washington Post/Getty Images)
WASHINGTON (AP) -- UPDATE: AU tweeted just before 9:30 p.m. a suspect has been placed in custody and the lockdown was lifted.
Police and school officials say American University's campus in the nation's capital is on lockdown after police received calls about a man with a gun.
That report came in to Washington police about 7:40 p.m. Wednesday, but authorities say officers have not confirmed the report and so far, no gunman has been found.
The university sent tweets saying the campus was in lockdown. It urged students to shelter in place, adding in a tweet that authorities were continuing to search for a possible armed person.