(CNN) — An argument between a Connecticut teenager and her mother’s boyfriend over his smoking in the house turned deadly when the man fatally shot the girl and her brother and then killed himself, according to the Watertown Police Department.
Della Jette, 15, and Sterling Jette Jr., 16, were taken on Tuesday night to Waterbury Hospital where they both were pronounced dead shortly after arrival, according to a news release from the Watertown Police Department. Their mother, identified by CNN affiliate WTNH as Danielle Jette, was in the home when the shootings occurred and called 911, police said. She was not injured.
Paul W. Ferguson, 42, was pronounced dead at the scene from an apparent self-inflicted gunshot wound to the head, police said in the news release.
He had moved into the home two weeks before the incident, police said.
The children’s father, Sterling Jette Sr., had fatally shot himself in the same home three years ago, police said.
Tuesday’s argument began around 9:45 p.m. when Della Jette became upset by Ferguson smoking in the house, Watertown police detective and spokesman Mark Conway told CNN.
Ferguson retrieved a handgun from his bedroom and shot Sterling Jette — who had attempted to intervene — in the leg, Police Chief John C. Gavallas said in a news conference covered by WTNH.
“The mother went downstairs to call 911 when she heard a second gunshot, presumably when he shot the daughter on the deck,” Gavallas said. “He came back in the house and shot the son in the chest.”
The teenagers’ deaths were ruled homicides by the Connecticut Office of the Chief Medical Examiner on Wednesday.
Ferguson was a convicted felon and not authorized to possess a firearm, according to police. He had been convicted of first-degree unlawful restraint after an arrest on a sexual assault charge in 2007, Conway said.
Officers found several guns in the house, according to CNN affiliate WFSB.
Both teenagers were students at Kaynor Technical High School, according to police.
In the 2016 shooting at the home, Sterling Jette Sr. died from suicide after a minor domestic dispute, Conway said.
“This mother is completely distraught as you can imagine,” Gavallas said during a press conference. “Boyfriend moves in the house two weeks ago for the holiday season. He’s gone and both her children are gone.”
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