A Virginia police officer was justified in fatally shooting a knife-wielding suspect who forced a woman from a car before holding another man hostage as a human shield, a prosecutor said Thursday.

St. Louis County Attorney Mark Rubin said officer Nick Grivna used deadly force as a “last resort” to stop 41-year-old J Scot Alan Widmark from potentially killing a random victim in the Nov. 27 incident.

“I have concluded that officer Grivna displayed superb training, courage, restraint, compassion and professionalism, and his actions were justified, lawful and therefore authorized under the law,” Rubin said. “He probably saved an innocent citizen's life.”

Grivna, a five-year veteran of the Virginia Police Department, fired a single shot from his duty rifle. A medical examiner concluded that the bullet initially struck Widmark’s hand before fragmenting and entering his head.

The Minnesota Bureau of Criminal Apprehension, which handled the investigation, completed its work on Dec. 20. Rubin conducted the legal review with the assistance of retired prosecutor Vern Swanum.

According to their findings:

A St. Louis County public health nurse was parked in a county vehicle on Third Avenue West, just below Second Street South, around 5 p.m. when she was approached by Widmark, who repeatedly demanded that she exit the vehicle.

The woman eventually did so, taking the keys with her. She ran north and was picked up by a passing motorist who noticed she appeared to be in distress. At the same time, the woman was calling 911.

Lt. Matthew Kelly of the the Virginia Police Department was first on scene. He reported that Widmark seemed to be staring him down before emerging from the car and producing a large knife from his coat.

Widmark was described as “waving the knife in a very threatening manner” as he began approaching the other vehicle. Kelly, who had unholstered his firearm, requested immediate backup.

Widmark ignored Kelly’s demands to stop and drop the weapon. Kelly, later explaining that he believed Widmark was trying to provoke him into firing, retreated and continued to give commands from a safe distance.

Widmark suddenly began running south on Third Avenue and approached a passerby, identified in the documents only by initials C.W.M. Kelly, who had given chase, tried to warn the man but Widmark grabbed him in a headlock with his left arm while continuing to brandish the knife in his right hand.

At that point, only 20 seconds had elapsed since Kelly first arrived on scene. He reported the hostage situation over the radio and requested a rifle.

Grivna, who was dealing with an arrestee at the nearby courthouse lock-up, hurried to the scene as Widmark continued to hold the man as a human shield. His squad car was equipped with a dash cam, but Widmark continued to walk backward out of frame with the hostage.

For just over a minute, Grivna could be heard attempting to negotiate with Widmark - who he mistakenly believed to be a man he knew from previous contacts as “Adam” - instructing Widmark to put down the knife and telling him “it’s not worth it.”

Eventually, Widmark and the hostage were backed up against a garage at 302 Third Ave. Officers reported that Widmark, who never said anything, became more aggressive in swinging the knife, appearing as though he would injure C.W.M.

Grivna “concluded he was out of options” and fired the rifle a single time. Widmark fell to the ground and C.W.M. was escorted to safety.

An ambulance was on scene within four minutes and Widmark arrived at Essentia Health-Virginia within 10 minutes of the shooting, but he was quickly pronounced dead. The medical examiner later concluded that the injuries were consistent with Widmark’s raised right hand being struck, with the bullet then entering his cheek and stopping in his skull.

Authorities said they were never able to determine Widmark’s motives, but he was found to have methamphetamine and synthetic opioid buprenorphine in his system. A brother also told investigators that he had long suffered from depression and drug addiction and had alienated most of his family.

The Virginia Police Department purchased body cameras for its officers in August, but Mayor Larry Cuffe told the News Tribune that technical requirements had prevented them from being implemented at the time of the incident.

Swanum, who has commonly been consulted to review police shooting cases, said it was clear from the evidence gathered that Grivna did not want to use deadly force and made multiple attempts to resolve the situation peacefully.

“Officer Grinva was facing a situation where a private citizen was in grave imminent danger of great bodily harm or death,” he wrote. “Officer Grinva, as well as other law enforcement officers on the scene, exhibited superb training, courage, restraint and professionalism. The decision by Officer Grinva to use deadly force was well-considered, and used as a last resort to protect the life of an innocent civilian.”