BUFFALO, Minn. (AP) — A man who stormed a medical clinic in Minnesota, fatally shot one person and wounded four others faces a mandatory term of life in prison without parole when he is sentenced Friday.

Gregory Ulrich opened fire Feb. 9, 2021, at the Allina Crossroads Clinic in Buffalo, a city of about 16,400 people that is 40 miles (65 kilometers) northwest of Minneapolis. A jury earlier this month found Ulrich guilty of the 11 charges against him, including premeditated first-degree murder for the death of Lindsay Overbay, a 37-year-old medical assistant.

Four other clinic staffers survived but suffered serious injuries.

During the trial, Ulrich, 68, admitted that he bought the gun, assembled pipe bombs and carried out the attack. However, he maintained that he was driven by excruciating pain that he said the medical team at Allina failed to properly manage and that he never intended to kill anyone.

Prosecutors argued Ulrich knew what he was doing that day. They played a pair of cellphone videos that Ulrich recorded of himself a couple of months before the attack where he said older people should grab their guns and go down to their clinics to kill as many nurses as possible if cut off from pain medication.

One witness testified during the trial that she heard the gunman call 911 and tell the dispatcher to “send a lot of ambulances. There are a lot of spinal injuries and I have bombs that are about to go off.”

Law enforcement said after the attack that Ulrich was known to them and had been angry over his medical treatment.

(Copyright (c) 2022 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

Join our Newsletter for the latest news right to your inbox