ROY, Utah — A Utah family of four was found shot to death in their home in what authorities believe is a murder-suicide, police said Monday.

Officers discovered the bodies of Russell Smith, 29; his wife, Shawna Smith, 26; and their children, 6-year-old Tylee and 2-year-old Blake on Sunday night. It appeared Russell Smith shot himself, and investigators were not looking for any suspects, police Lt. Kevin Smith said.

The department received a 911 call about an assault at 10 p.m. Sunday from a relative who stopped by the house in Roy, a city about 32 miles north of Salt Lake City.

There was no history of police responding to the home near Roy High School, Smith said. Investigators talked to family members and were trying to uncover a motive.

The relative who discovered the family decided to come by the house after failing to hear from anyone there since an afternoon text message, said Smith, who is not related to the family. He declined to specify the person’s relationship to the victims or what the text message said.

Neighbor Lynn Everley, 68, said the Smiths were a quiet, young family, and he had never heard any fights or seen any indication of problems.

Everley said Russell Smith worked in the nearby city of Ogden at a company that recycles outdated military supplies, while Shawna Smith worked at a child care facility. Everley said the family lived in the home for at least several years — as long as he had been in the neighborhood.

“They’re a couple that you would never have expected this to happen,” Everley said. “But then, what makes a person snap?”