MANCHESTER, Tenn. -- A soldier is accused of killing his girlfriend and her two young children, stuffing their corpses into plastic garbage bags and hiding them in a closet for days.

A neighbor says he noticed an unusual stillness at the house normally busy with the toddlers and their friendly mother. When police in this small town investigated a missing person's report Wednesday night, they said they found a "very gruesome" crime scene that rattled even veteran investigators.

"It's the worst I've seen, and I've been here 30 years," said Ray Stewart, a police investigator in this town of 10,000 that hosts the Bonnaroo Music and Arts Festival each summer.

Manchester Police Chief Ross Simmons identified the victims as 26-year-old Stephanie Hershman and her sons, 3-year-old Jathan and 1-year-old Jaylon.

Police said 30-year-old Matthew Perkins, of Tullahoma, told someone Wednesday night that he had killed the family, and the person went to police. The U.S. Army recruiter who has served overseas is charged with three counts of first-degree murder and is being held in the Franklin County jail on a $6 million bond.

His arraignment was set for Tuesday. A spokeswoman for the clerk's office said it wasn't known if Perkins had an attorney.

Police believe the three were killed on Sunday. They did not release a cause of death but said the bodies have been turned over to a medical examiner.

Perkins was not the children's father. Investigator Billy Butler said Perkins is separated from his wife of 10 years, Jennifer Perkins. She was at the police station for questioning on Thursday morning, but declined to be interviewed by a reporter.

Butler said the couple have two children and that Jennifer Perkins described her husband as a good father.

The slain children's father, Jeremy Hershman, is currently incarcerated on drug charges, Simmons said. Police said he is very distraught.

Mark Shannon lives across the street from the Hershmans in the community about 65 miles southeast of Nashville. He said he usually saw Stephanie Hershman on her porch smoking when he was taking his children to school. Some mornings Perkins was there, too.

But he hadn't seen anyone at the house the past couple of days. It was normally busy, with people going in and out, he said.

"We'd see her and her kids out playing and we'd wave back and forth," he said.

Of the crime, he said, "It's unnerving, to say the least."