12:20 p.m. OU President David Boren said Gould Hall has been searched by police officers and SWAT team members and they've found no evidence that any shots were fired. Regular campus operations are being resumed, with the exception of Gould Hall, where authorities continue to search.
Boren said he's not sure the origin of the noises that students reported.
12:10 p.m. OU police have issued an alert asking students to continue to avoid Gould Hall, but otherwise to resume normal activities on campus.
12:05 p.m. Joey Stipek, an OU journalism student, said armed authorities entered Gould Hall about 11:45 a.m.
Students in nearby Gaylord Hall were told to stay inside.
Stipek said he and other students went outside when they heard sirens. There was no initial indication of injuries or anyone transported.
Alec Polk, an Edmond freshman, said he heard three gunshots and people ran into nearby buildings.
11:50 a.m. Dozens of emergency vehicles and personnel are on the scene. Multiple sources have reported hearing shots fired.
Gould Hall on the South Oval houses the College of Architecture.
11:35 a.m. NORMAN — University of Oklahoma police are responding to reports of possible shots fired on campus, Major Bruce Chan said.
University spokeswoman Catherine Bishop confirmed there are reports of shots fired in the vicinity of Gould Hall.
One OU official said, “We are all on lock down. Scary deal.”