ROTTERDAM — The police officers who confronted an emotionally disturbed, knife-wielding man in a town home over the weekend initially tried to subdue the man with a stun gun but it failed to stop him and they fatally shot him, a State Police official said.

At a news conference Wednesday morning, Major William Keeler said the investigation is "99.9 percent complete" and troopers have found police were justified in shooting William J. Clark III.

The deadly encounter about 11:30 a.m. Sunday at 1061 Roberta Road occurred after Clark, 30, allegedly slashed a town police officer.

Rotterdam police and a deputy from the Schenectady County Sheriff's Office had been called to the home after Clark's mother reported her son was armed with knives and was smashing furniture.

When police arrived, Keeler said, Clark was hiding. Two town police officers found him behind a door in a bedroom.

"They pleaded with him, 'Please drop the weapons and let us help you,'" Keeler said.

But Clark came out from behind the door and attempted to stab a sergeant with a knife. The officer's safety vest blocked the blow but Clark slashed the other officer in the back of his head, Keeler said.

He said the officers fired a stun gun but only one of the prongs hit Clark, who was wearing a baggy sweater. Unable to deliver a debilitating shock, one of the officers fired his gun, hitting Clark in the torso and head. Four shots were fired.

The officer, who Rotterdam police have not identified, suffered a cut to the head that required stitches, police said.

State Police are investigating the shooting.

Rotterdam Police Chief James Hamilton said the two town officers are on paid administrative leave while the investigation continues.

"It's a very difficult situation," Hamilton said.

State Police said Clark's mother moved into the house a month earlier. Clark, who police confirmed had served in the military, had a history of mental health problems.

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