BUTLER TWP — An off-duty trooper shot his .380-caliber pistol six times at an alleged suicidal neighbor who showed up at the officer’s home last weekend with an Airsoft gun, according to a state police investigation.

Kristopher A. “Kit” Barkus was hit twice, once in his lower right abdomen and once in his chest, after pointing the gun at Trooper Brian Knirnschild.

The shot that struck Barkus’ chest also hit his spine, state police Cpl. Dan Herr said Wednesday. That likely was the fatal shot, investigators believe.

The findings into the death of the 25-year-old man, which has been ruled a homicide, are included in a report of the Friday night shooting at Knirnschild’s home on September Drive in Butler Township.

Police on Wednesday completed their investigation after interviewing Knirnschild at the barracks. Later that day, they turned over their report to Butler County District Attorney Richard Goldinger, who reviewed the findings with investigators.

It is now up to Goldinger to determine if Knirnschild was justified in using deadly force against Barkus.

Before meeting with police, Goldinger said when he reaches a decision, he would release a statement explaining his rationale behind his conclusion.

“I may ponder the report for a few days, I’m not sure,” he said Wednesday. “I’m not going to make a rush decision.”

Knirnschild told authorities that shortly after 8:30 p.m. Friday he noticed his young daughter at the front door pointing outside.

The 27-year-old trooper went to the door and spotted Barkus with what appeared to be a gun.

It was not immediately known why Barkus went to Knirnschild’s house; however, family members acknowledged that Barkus suffered from depression and had threatened to kill himself that night.

Knirnschild said he “started to issue commands for Barkus to drop his weapon” and then fired his own pistol, according to court documents filed by state police as part of their investigation.

Police this week disclosed that Barkus was carrying a Powerline Airstrike 240 air gun, which resembles a Beretta 92FS handgun.

“That (Airsoft) gun looks very real,” Herr said.

About two hours after being shot, Barkus was pronounced dead at Allegheny General Hospital in Pittsburgh.

An autopsy ruled that he died of a gunshot wound “to the trunk,” the Allegheny County Medical Examiner’s Office said.

Police on Saturday got search warrants for the Knirnschild and Barkus homes, which are just several houses apart on the same side of the street.

The evidence they collected was disclosed in recently filed court papers.

At Knirnschild’s house, police recovered his pistol and five .380-caliber casings.

However, police believe the trooper fired six times. Herr speculated that police have been unable to locate the sixth casing.

Knirnschild’s magazine clip holds six rounds, police said. The clip was empty when police found it.

“(Knirnschild) was shooting to stop the action, and the action was still occurring at the time,” Herr said in explaining why the trooper shot six times.

The “action,” Herr said, was Barkus initially pointing a gun, that looks like a real one, at Knirnschild.

Barkus at some point put the gun to his own head, before pointing it back at Knirnschild.

Investigators believe the trooper was on the first or second step outside the front door when he fired. Knirnschild was “no more than 10 yards” from Barkus, Herr said.

Two of the shots hit Barkus and two others hit a black backpack that he carried with him to Knirnschild’s house, Herr said.

Police did not know where the other shots went.

Two of the slugs were in Barkus’ back pack that contained a laptop computer and several bottles of medication prescribed to him.

Two other slugs were found at the scene, on the sidewalk and in the yard, Herr said. Investigators believe one of those slugs was from a “through-and-through” shot that hit Barkus in the abdomen.

The autopsy found the fifth slug in Barkus’ body.

Herr said they have found no one who witnessed the shooting.

But it turned out that Barkus’ older brother, Bobby, was in his car in Knirnschild’s driveway at the time of the gunfire.

But ”vegetation” — bushes, shrubs and trees — blocked Bobby’s line of vision, and he didn’t see the shooting, Herr said.

Bobby Barkus had pulled into the driveway looking for his younger brother, who had just left the family house, telling Bobby’s fiance that he was “going to jump off a bridge,” police said in search warrant applications.

Bobby drove his wounded brother to Butler Memorial Hospital.

But investigators were not certain how Kristopher made it to the car.

Bobby told investigators that his brother got into the car on his own, Herr said. But a witness told police that Bobby may have assisted Kristopher into the vehicle.

Police said that investigators interviewed Bobby for about an hour. He was never arrested and has not been charged.

“He was cooperative for the most part,” Herr said of Bobby.

Robert Barkus, Kristopher and Bobby’s father, attended his son’s funeral Wednesday and was unavailable for comment.

Police suspect that Kristopher’s mental health issues, for which he was taking numerous prescription medication, were a likely factor in the shooting.

Investigators said evidence of that was found in the backpack and at his own home.

Among the prescriptions that police seized were fluoxetine and mirtazapine. Police did not know the reasons why Barkus was taking those drugs.

However, according to WebMD, fluoxetine and mirtazapine are used to treat a variety of conditions, including depression and other mental/mood disorders. The medications can also help prevent suicidal thoughts.

At the home, police said they found suspected drug paraphernalia belonging to Barkus, including a small tube with “white residual powder,” and a syringe and a spoon that held a cotton swab, documents said.