CASPER, Wyo. (AP) — A man was arrested Monday after he fired a handgun inside a hospital, police said.

Nobody was hurt in the shooting around 1 a.m. at Wyoming Medical Center in Casper.

Mitchell D. Taylor, 20, of Casper, faces charges including aggravated assault, use of firearm while committing a felony, and felony property damage, according to police. There was no immediate information on whether he had an attorney who could comment.

Police arrived at the hospital's emergency room and found signs of shots fired in the radiology department. They took Taylor by surprise in a mechanical area on the hospital campus and subdued him with a Taser, Casper Police Chief Keith McPheeters said in a news conference at the hospital.

Emergency room staff evaluated Taylor before police took him to jail.

Police recovered the gun. They believe Taylor acted alone. His motive was unknown but being investigated, McPheeters said.

Yolanda Isaldo said she was in the emergency department of the hospital and heard seven gunshots.

A nurse was getting ready to discharge her when they heard a loud bang and a scream, she and J.R. Isaldo told the Casper Star-Tribune. The nurse left to investigate and the couple barred the door with a hospital bed and turned off the lights.

They said they could not leave the hospital until about 2:30 a.m. when police lifted a lockdown.