A man armed with a handgun went on a house-to-house shooting spree in a rural town in the US state of Missouri, killing seven relatives and neighbours before taking his own life, officials said on Friday.

All of those killed by the gunman, identified as Joseph Aldridge, 36, lived within a few miles of each other in the tiny community of Tyrone, an unincorporated area with a population of about 50, authorities said.

Authorities said the motive was unclear and declined to comment on whether the murders had been triggered by the death of Aldridge's mother, who was found at her home. Authorities said she may have died from natural causes.

"It's heartbreaking," said Todd Haley, senior pastor at Ozark Baptist Church, about three miles from Tyrone. "Anytime you see families that go to this level of violence, it's a shame."

The events, which police said were spread over six crime scenes, began unfolding around 10 p.m. on Thursday when a girl called 911 from a neighbor's home.

A man who declined to be identified told a Reuters photographer that a teenaged girl in a nightgown came to his house, running barefoot through a snowy wooded area and crying that her parents had been shot. She called police and deputies found her parents dead at their home.

Authorities said they later discovered five other people dead and a wounded woman in three other houses. The woman, who is expected to recover, gave them information about the shooter, Texas County Sheriff James Sigman said.

Four of the victims were identified as Garold Aldridge, 52, his wife Julie Aldridge, 47, Harold Aldridge, 50, and his wife Janell Aldridge, 48. The names of the other victims were not released.

There was no sign of forced entry in any of the houses, Sigman said, adding that the killings had shattered a sense of safety in the town. "Start locking your doors. The world is changing. You got to be safe," he said.

Authorities said an autopsy would be done on Saturday on the body of Joseph Aldridge's 74-year-old mother, Alice Aldridge.

Joseph Aldridge's body was discovered with a self-inflicted gunshot wound in a pickup truck parked on a highway in nearby Shannon County, authorities said. Sigman said Aldridge had a minor criminal history.

Tyrone is about 160 miles southwest of St. Louis, near the Mark Twain National Forest, and attracts hunters, campers, and river rafters. Texas County where Tyrone is located has a population of roughly 24,000 people.

"Everybody knows everybody here. We all cry together," said Scott Dill, superintendent of the Houston School district in Texas County.

Charles Smith, who lives a few miles from the shootings, said the Aldridge family seemed like good people. "They would help you out when they could, just like we all do down here in the country," he said. – Reuters