A man who got into an argument with his estranged wife over their children was arrested on Sunday after a house-to-house shooting rampage in rural Mississippi that left eight people dead, including his mother-in-law and a sheriff’s deputy.

“I ain’t fit to live, not after what I done,” a handcuffed William Corey Godbolt, 35, told a reporter from the Clarion-Ledger newspaper.

The shooting began on Saturday night at a home in Bogue Chitto after the deputy arrived in response to a domestic disturbance call, and spread to two houses in nearby Brookhaven, about 70 miles south of Jackson, the state capital.

The dead included two boys, investigators said. Godbolt was hospitalized in good condition with a gunshot wound. It was not clear who shot him.

A Mississippi Bureau of Investigation (MBI) spokesman, Warren Strain, said prosecutors planned to charge Godbolt with murder but that it was too soon to say what the motive was. Authorities gave no details on his relationship to the victims.

Willie Corey Godbolt. Photograph: MBI/AP

However, a witness and Godbolt himself shed some light on what happened, with Godbolt giving an interview as he sat with his hands cuffed behind his back on the side of a road, surrounded by law enforcement officials. He was talking to his wife and in-laws, he said, when somebody called authorities.

“I was having a conversation with her stepdaddy and her mama and her, my wife, about me taking my children home,” he said. “Somebody called the officer, people that didn’t even live at the house. That’s what they do. They intervene.

“They cost him his life,” he said, apparently referring to the deputy. “I’m sorry.”

The stepfather-in-law, Vincent Mitchell, said Godbolt’s wife and their two children had been staying at his Bogue Chitto home for about three weeks after she left her husband because of domestic violence.

When the sheriff’s deputy arrived at the house, Godbolt looked as if he were about to leave then reached into his back pocket, pulled a gun and opened fire, Mitchell said.

Mitchell said he escaped along with Godbolt’s wife. But he said three family members were killed in his home: his wife, her sister and one of the wife’s daughters.

“I’m devastated,” Mitchell said outside his yellow frame house, in a community of modest houses, trailer homes and small churches set among thick woods. “It don’t seem like it’s real.”

People console each other near a house where several people were killed in Lincoln County, near Brookhaven. Photograph: Rogelio V Solis/AP

After fleeing his in-laws’ house, Godbolt killed four more people at two other homes, authorities said. At least seven hours elapsed between the first shootings and Godbolt’s arrest near the third and final crime scene in a subdivision of ranch houses in Brookhaven, a few miles from Bogue Chitto.

“It breaks everybody’s heart,” said Garrett Smith, a 19-year-old college student who went to high school with one of the victims. “Everybody knows everybody for the most part.”

The deputy, William Durr, 36, had served two years in the sheriff’s department and had previously worked as a Brookhaven police officer. Lincoln County Sheriff Steve Rushing said Durr was married and had an 11-year-old son.

“He had a heart of gold,” Rushing told the Daily Leader. “He loved doing anything with kids. He would go out of his way to help anybody.”

Off duty, Durr was a ventriloquist who took his puppets to schools and churches and performed for children.

Godbolt said he did not intend for police to capture him alive.

“My intentions was to have God kill me. I ran out of bullets,” he said. “Suicide by cop was my intention.”