Reuters reports the massacre on Wednesday (local time) has stunned the close-knit community of Enoch City in southwestern Utah, where both the mayor and the city manager said they knew the Haight family as neighbours.
After reporting the shooting with scant details, city officials called a news conference on Thursday and identified the shooter as Michael Haight, the father of the five children he killed.
Haight also shot dead his wife, Tausha Haight, 40, and her mother, Gail Earl, 78.
The children killed were a 4-year-old boy, a 7-year-old boy, a 7-year-old girl, a 12-year-old girl and a 17-year-old girl, officials said without naming them.
"The Haights were my neighbours. The youngest children played in my yard with my sons," Enoch City Mayor Geoffrey Chesnut told reporters. "Enoch City is a very close community. The neighbours are good. The people are wonderful. And the effort we make on one another's behalf is like family."
The rural town of about 7,500 is home to a high number of young professionals with children, Chesnut said.
Police were sent to the home for a welfare check after Tausha Haight had missed an appointment in town and efforts to reach her had failed, Chesnut said.
Tausha Haight and one of her daughters had been seen at a church event on Tuesday night, Chesnut said.
Officials declined to draw conclusions about the impact of the divorce petition that they said had been filed on December 21.
Police Chief Jackson Ames said officers were once called to the couple's home a couple of years ago for an incident that he declined to describe, but that there had been no recent complaints.
"From what we saw outside, they were just phenomenally kind, and so everyone I've talked to has just been absolutely shocked about losing them," neighbour Garrett Minkler told ABC4 television.
School officials said counsellors were being made available to classmates of the victims.
City Manager Rob Dotson noted that officials at the news conference were misty-eyed, their voices cracking, because of the emotional toll.
"We don't know why this happened," Dotson said. "However, we do know that they were our friends. They were our neighbours. And that we loved them."
Rob Dotson (right), Enoch City manager holds a news conference at city hall along with Geoffrey Chesnut, Enoch Mayor, Jackson Ames, Enoch Chief of Police and Tim Marriott (left), Iron County School District Counsellor, on the murder of eight people in the same family on January 5, 2023 in Enoch, Utah. Photo: GEORGE FREY