Motive revealed in horrifying LI murder-suicide as cops ID killer as former EMT Joseph DeLucia Jr., who slaughtered relatives after mom’s death

A former EMT slaughtered three of his siblings and a niece as they gathered at their deceased mom’s Long Island home to discuss plans for her estate — and the killer was apparently upset that he’d have to leave the house after they sold it, authorities said Monday.

The shooter — 59-year-old Joseph DeLucia Jr. — had lived with his 95-year-old mom, Theresa DeLucia, until her death early last week, Nassau County Police Capt. Stephen Fitzpatrick said at a press conference.

But if the family sold the house, he’d need to find somewhere else to live — and DeLucia had nowhere else to go.

In his rage, DeLucia leveled a pump-action Mossberg 12-gauge shotgun at his three siblings — Joanne Kearns, 69, of Tampa, Florida; Frank DeLucia, 64, of Durham, North Carolina; and Tina Hammond, 64, of East Patchogue — and gunned them down in the house’s den , Fitzpatrick said.

Joseph DeLucia, auto mechanic and former EMT who killed 4 in LI murder-suicide, was a hoarder: cops

He also murdered his niece, 30-year-old Victoria Hammond of East Patchogue, before running out to the front yard and turning the shotgun on himself, Fitzpatrick said.

“Officers found him with a self-inflicted gunshot wound to his chest,” the captain said. “He was pronounced at the scene.”

Police identify victims in LI family murder-suicide

A neighbor called 911 when they heard DeLucia screaming in the yard — just before he killed himself.

“We heard a high-pitched scream, it was Joe screaming, then one shot. I was shocked. I never would have thought beforehand that this would happen,” neighbor Sandy Landsman, 73, told The Post. “His mother died last week. The siblings were getting ready to sell the house.

“We heard he was very upset over this,” Landsman continued. “He didn’t know where to go, he had lived there his whole life. One of the siblings said she would take care of him, that she would let him come and live with her. Apparently, that didn’t sound too good to him.”

Fitzpatrick said investigators have been told that DeLucia had past mental health problems, but cops have not confirmed that.

Neighbors buttressed this, saying the former EMT suffered from mental illness that had been exacerbated by his sorrow over his elderly mom’s recent death.

“There were challenges. It’s really sad,” said Wendy Paisner, who lives across the street from the grisly scene. “But his mother passed away and I think that triggered him. You know, that they were selling the house.”

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A local real estate agent, Mary Macaluso, told Newsday that the late matriarch’s kin contacted her to swing by the home Sunday in preparation for selling the property. But when she got there that afternoon, police had already taped off the street.

“When this happened, they arrived to meet the realtor,” Fitzpatrick said. “They brought Starbucks, they were assembled in the den area — the brother had stayed behind.”

DeLucia fired 13 shots in total — 12 aimed at the victims, and one for himself, the captain said, meaning he had to reload at least once.

There had been only one prior call to the house — a 2022 wellness check that didn’t lead to any police action, Fitzpatrick said.

DeLucia was also arrested for drunk driving in 1983. Other than that, his record was clean.

“In 41 years, that was one of the most horrific scenes I’ve ever seen,” Nassau Police Commissioner Patrick Ryder said .

Additional reporting by Isabel Keane

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