An investigation by the Office of the Maine Attorney General found a state police detective was justified when he shot an armed man in Chelsea last year. The armed man then shot and killed himself after the detective’s gunshot.

Police Detective Scott Duff “reasonably believed” that Frank Foss Jr. of Dresden “was about to shoot him” during the July 23 incident, according to the office’s report, which was released Friday.

Duff acted in “self-defense” by firing at Foss twice after Foss did not surrender to police and pointed a gun at Duff, the report says.

Foss, who was 28 at the time, fatally shot himself in the head with his .45 caliber handgun after Duff fired at him, according to the report.

An autopsy performed the day after the shooting ruled Foss’ death a suicide by gunshot wound to the head, and also found a nonfatal gunshot wound to the abdomen.

“All the facts and circumstances point to the conclusion that detective Duff reasonably believed he was acting in self-defense at the time he used deadly force,” the report concluded.

Duff was placed on administrative leave while the Office of the Maine Attorney General investigated the incident, a standard practice for officer-involved shootings, the Kennebec Journal reported previously.

He returned to work Sept. 6, a Department of Public Safety spokesperson said in September.

Duff was previously involved in two other shootings, both of which were deemed justified, the Kennebec Journal reported in the days following the Chelsea incident.

The July shooting ended a weekslong, multi-agency search for Foss, who was wanted for violating conditions of his release and illegally possessing firearms. Foss was not allowed to have firearms due to three 2020 felony convictions, according to previous Kennebec Journal reports.

The search began July 2, 2023, when Lincoln County sheriff’s deputies responded to a Dresden residence for a report that Foss was intoxicated and had a gun, according to the attorney general’s report. Police did not locate Foss, but heard several gunshots in the area.

Investigators found evidence that Foss was in possession of firearms at his home on Calls Hill Road in Dresden and in his girlfriend’s vehicle, according to the report.

On July 7, Foss’ girlfriend told police that Foss was planning on killing himself in the woods and that “he would definitely try suicide by cop,” according to the report. She also told investigators that she did not know Foss’ whereabouts and that he did not have a cellphone.

Cellphone records subsequently obtained by police found that Foss did in fact have a cellphone, and was communicating with his girlfriend to bring ammunition and alcohol to him, the report says.

The cellphone records also show that Foss was near his Dresden residence at the time, where a state police tactical team attempted to execute a search warrant but could not locate Foss, according to the report.

On July 23, with the assistance of the FBI, the Lincoln County detective located Foss’ cellphone near a residence on Hankerson Road in Chelsea owned by his girlfriend’s parents, according to the report.

The state police tactical team, including Duff, searched the “thickly wooded” area near the property and eventually located Foss, the report says.

Duff was alone when he encountered Foss because the other members of the team were searching with a dog in another area, according to the report.

Foss was moving “intentionally and slowly” while walking in Duff’s direction but did not appear to see Duff, according to the report. Duff identified himself as an officer and told Foss to stop moving, but Foss did not comply and pointed a firearm at Duff, the report says.

Duff, who was in a “seated position,” then fired at Foss from about 10 to 12 yards away from Foss, the report continues.

“Detective Duff said he used deadly force on Mr. Foss to protect himself from being shot,” the report says. “Detective Duff said he yelled to Mr. Foss to show him his hands, but got no response.”

Foss was a graduate of Hall-Dale High School in Farmingdale and a military veteran, his lawyer told the Kennebec Journal after his death.

His girlfriend, Annie McKechnie of Chelsea, was arrested in September on a charge that she helped Foss evade police.