DENVER (AP) — A Denver hospital went on lockdown Friday afternoon after a report that a man was seen carrying a rifle on the complex grounds, and police said they were conducting a standard room-by-room search.

Investigators did not confirm that shots had been fired or anyone was injured at Rose Medical Center, police spokeswoman Raquel Lopez said. Hospital officials said no one there was hurt.

Police officers carrying long guns surrounded the facility east of downtown after the sighting, and several roads near the building were closed and blocked by patrol cars.

Armed officers climbed to the roofs of buildings, and authorities said the way they were searching the hospital was standard protocol.

An adjacent Veterans Administration hospital also was on lockdown as a protective measure. The scene outside was calm by Friday evening.

Denver police Officer Tyrone Campbell said police received multiple telephone calls reporting shots had been fired in the area surrounding the medical center shortly after 4:15 p.m.

He declined to say whether police had determined if shots had been fired, saying they were investigating. Authorities were looking for a man seen with a gun, he said.

The man was described as a white male in his mid-30s wearing a flannel shirt and a hat.