Updated

Prosecutors have announced charges Thursday against Gregory Paul Ulrich, the 67-year-old accused of killing one and injuring four after opening fire at a Minnesota health clinic this week. 

criminal complaint filed in Wright County states that Ulrich has been charged with second-degree murder, four counts of attempted murder and one count each of felony use of an explosive device and carrying a pistol without a permit. 

The incident unfolded Tuesday at an Allina Health clinic in Buffalo, outside of Minneapolis. 

Gregory Paul Ulrich is shown here following his arrest Tuesday after a shooting at a health clinic in Buffalo, Minn. (AP/Wright County Sheriff's Office)

Gregory Paul Ulrich is shown here following his arrest Tuesday after a shooting at a health clinic in Buffalo, Minn. (AP/Wright County Sheriff's Office) (Wright County Jail)

MINNESOTA HEALTH CLINIC SHOOTING SUSPECT COMPLAINED ABOUT DOCTORS, THREATENED VIOLENCE IN THE PAST, REPORTS SAY 

The second-degree murder charge carries a maximum sentence of 40 years, while the other charges carry fines and sentences of up to $100,000 and 20 years, respectively. 

In a probable cause statement, a Wright County Deputy Sheriff wrote that Ulrich called 911 following the shooting and told dispatchers to have responding officers "back away and he would surrender." Ulrich later was taken into custody without incident, it added. 

During a search, Ulrich was found to be in possession of Smith and Wesson 9mm pistol ammunition and two marijuana cigarettes, the complaint says. He also reportedly told investigators that he traveled to the health clinic on public transportation and police say surveillance footage showed him stepping onto a bus while "wearing a heavy brown jacket and carrying a briefcase." 

When officers arrived in the aftermath of the attack, the victims were "screaming for help" and police observed that "multiple areas of the clinic were damaged from apparent ammunition rounds and explosions" and that an "undetonated improvised explosive device was located near the briefcase," the complaint adds. 

Law enforcement personnel walk toward the Allina Health clinic on Tuesday following the shooting there. (AP/Star Tribune)

Law enforcement personnel walk toward the Allina Health clinic on Tuesday following the shooting there. (AP/Star Tribune)

Prosecutors say Ulrich first started opening fire after walking into the clinic and being asked by its staff if he needed help. 

The complaint says Ulrich then worked his way through the clinic -- at one point firing two shots into the leg of a victim who was trying to run away from the scene. Two explosive devices were said to have been detonated by him during the chaos. 

"A preliminary examination of the defendant’s cell phone recovered from the clinic revealed a recording made by the defendant consisting of a rambling video message that alluded to an incident at the clinic," the complaint said. 

MINNESOTA HEALTH CLINIC SHOOTING SUSPECT HAD HISTORY WITH FACILITY, POLICE SAY 

Police previously said Ulrich was upset with health care he had received, but have not yet announced the motive for the attack. Those who knew him also told news outlets yesterday that Ulrich had been complaining that doctors weren’t giving him enough pain medications. 

Investigators that searched Ulrich’s last known address found gunpowder consistent with what was discovered inside the explosives and also found an empty box of ammunition at a motel he was staying at prior to the shooting, prosecutors allege. 

Law enforcement personnel and first responders gather outside of the Allina Health clinic Tuesday. (AP/Star Tribune)

Law enforcement personnel and first responders gather outside of the Allina Health clinic Tuesday. (AP/Star Tribune)

The victim who died -- identified by Allina Health as medical assistant Lindsay Overbay -- was struck by one bullet that entered her abdomen and passed through her liver and spine before leaving her body, the complaint states. 

"With overwhelming sadness, we can confirm that Lindsay Overbay lost her life to this senseless act of violence," the health provider said in a statement Wednesday. "Lindsay was a medical assistant who worked for Allina Health since November of 2018. The loss of Lindsay is traumatic for all who knew and loved her. Our entire Allina Health family extends our deepest sympathies to her family, friends and co-workers." 

Allina Health said the other victims -- including one prosecutors say is currently hospitalized after being struck six times by gunfire – are all staff from the company. 

"Even though this appears to be an isolated incident, we have taken the extra precaution of increasing security in our facilities," its statement said. "We are working closely with law enforcement who are providing additional support to ensure the safety of our teams and patients." 

Overbay, a 37-year-old nurse with two young children, was killed on Tuesday. (AP/Naiya Stubbe)

Overbay, a 37-year-old nurse with two young children, was killed on Tuesday. (AP/Naiya Stubbe)

Overbay, 37, is a mother of two who leaves behind her husband and two children – both under 10 years old, according to Fox9

Naiya Stubbe, a family friend, told the station that "the world lost a very beautiful, wonderful person" who deeply cared for her children and for others. 

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"She’s the best mother in the world," Stubbe said. "Can’t think of a better one." 

Ulrich, meanwhile, has had his bail set by a judge at $10 million, following a court appearance Thursday morning. He is due back late next month, Fox9 reports.