LONDONDERRY, N.H. — A man who fatally shot a heating oil company employee who went to his house to do work and then shot and wounded himself has died of his injuries, authorities said.

The homeowner, Richard Verville, who suffered from significant mental health issues, killed the worker, tried to kill himself and engaged police in an hours-long standoff at his home in Londonderry on Tuesday, they said. Verville, 69, was hospitalized in Massachusetts and died there on Wednesday, they said.

Police and SWAT team members had responded to Verville’s home on Tuesday. The neighborhood was evacuated, and several nearby schools were placed on lockdown because of the police activity in the area.

Neighbors told police that a City Fuel van pulled up to the home and they heard gunfire a short time later.

The attorney general’s office said Verville shot and killed Daniel Rabideau while Rabideau was working on his heating system before shooting himself.

“What looks like happened is, the homeowner shot a person who came into the home to perform some services, and then he turned the gun on himself, so it looks like it was an intended murder-suicide,” Senior Assistant Attorney General Jeffery Strelzin said.

Rabideau’s widow, Carole Rabideau, of Manchester, where City Fuel is based, said she was unaware of any previous contact between her husband and Verville. She said her husband, who was 59, didn’t deserve to die.

“If he was aware or unaware of what was happening, I can only pray to God he did not,” she told WMUR-TV.

She said that except for driving in the winter, she never worried about her husband’s job being dangerous.

“I remember my husband always, always telling me in the wintertime how many senior citizens he would go and give heat to,” she said.

Neighbors described Verville as paranoid. They said he moved into the neighborhood in 2012 and handed out letters in which he said he was under government surveillance.

Kurt Kiley, who lives across the street, told the Eagle Tribune he had a no-trespass order against Verville, who he said threatened him in the past.

“He goes from ‘Hey, how’s it going?’ to a whole different world — ‘(Expletive) you. I’m going to kill you.’ It’s like flipping a light switch,” Kiley said.

It was unclear what sparked the shooting.

Copy the Story Link