Although police shut down several areas on campus Friday after a man with a rifle was reportedly seen near the Administration building, no gunman was found, authorities said.

The 911 call prompted the lockdown and evacuation of the Administration building. Officers also evacuated the Student Union Memorial Center, the Modern Languages building and the UA Mall.

The call came in to the 911 system from a third-party operator to the University of Arizona Police Department at 4:52 p.m. indicating there was a man with a gun strapped to his chest and carrying a rifle, said Sgt. Joe Bermudez, a spokesman for UAPD. The caller also said a shooting in the administration building had occurred.

UAPD and Tucson Police Department officers began securing the area and sent out the first of a series of alerts via text message and email just after 5 p.m.

No shots were heard and no unusual activity was seen exiting the building, Bermudez said.

Officers searched the Administration building floor by floor and room by room. The TPD bomb squad and the Pima County Regional bomb squad were called to assist with the search as a precautionary measure, Bermudez said.

State Rep. Ethan Orr, who was on the third floor of the Administration building at the time of the call, said he waited in an office and called UAPD to report his location. When Orr received the text to evacuate, he and five people exited.

“You just don’t know. Every noise could be the police clearing the building, it could be a man with a rifle, or it could be a random noise,”Orr said. “You just don’t know.”

The search concluded at about 8:05 p.m., Bermudez said. Officers did not find a gunman or any signs of a shooting.

All restrictions were lifted and the student union reopened shortly after 9 p.m., about four hours after the 911 call.

Early in the search, authorities said there were multiple 911 calls about a shooter, but later changed the statement to say there had only been one reported sighting of a gunman. Officers declined to comment on whether or not the call was a hoax, adding that the investigation is ongoing.

For more coverage: See the video of UAPD’s press conference after the search ended or see the photo gallery of the incident.