The Southwest Missouri murders which happened this week involved a door-to-door killing spree, leaving seven people dead. According to the county coroner Friday, the Southwest Missouri murders may have been triggered after the gunman found his mother dead in her home, who allegedly died of natural causes.

All those involved in the Southwest Missouri murders lived within a few miles of each other in the small community of Tyrone, an area with a population of about 50, authorities said.

The gunman in the Southwest Missouri murders was identified as 36-year-old Joseph Aldridge. He was later found dead from a self-inflicted gunshot wound inside his vehicle east of Texas County.

The Southwest Missouri murders, spread over six crime scenes, started around 10 p.m. Thursday after a 15-year-old girl called 911 from a neighbor's home, according to Reuters.

She said she heard shots inside her house. She reportedly fled to a neighbor's home to call the sheriff's office, according to Texas County Coroner Tom Whittaker, as told to KSDK-TV's Mike Rush.

The unidentified neighbor told the Springfield News-Leader that the girl, crying, knocked on his door in the middle of the night and told him that her mother and father had been shot.

"She was barefoot, in a nightgown with no sleeves at all and her legs were all scratched up from briars," said the neighbor. "She said she seen a man in her dad's bedroom, talking to him in a normal voice. Then she said she heard gunshots and screaming."

In the course of over three hours, deputies soon found two bodies, a man and a woman at the first house. Five more bodies soon followed at three more homes. In addition, one woman was reportedly hospitalized with multiple gunshot wounds after the Southwest Missouri murders.

Some had been shot in the head and all victims had been shot by a large caliber handgun, reported USA Today.

Four of the victims of the Southwest Missouri murders were identified as Garold Aldridge, 52, his wife Julie Aldridge, 47, Harold Aldridge, 50, and his wife Janell Aldridge, 48. Names of the other victims have still not been released.

"In our job we see a lot of bad stuff, and this is bad, this is also hard on the police officers who are working that there," said Highway Patrol Sgt. Jeff Kinder. "It's not natural to see that sort of thing."

There was no sign of forced entry in any of the houses, Texas County Sheriff James Sigman said. He added that the Southwest Missouri murders ultimately shattered any sense of safety in the town.

"Start locking your doors. The world is changing. You got to be safe," he said.

According to authorities, Aldridge's motive for the Southwest Missouri murders remains unclear.

They have also declined to comment on speculations of the Southwest Missouri murders had been triggered by the death of Aldridge's mother, 74-year-old Alice Aldridge.

She was found dead on her couch inside their small wood-frame house, said Sigman Friday. She may have died from natural causes, according to authorities. Whittaker said she had been under a doctor's care and had been dead at least 24 hours. There were also no visible signs of trauma.

An autopsy would be done Saturday on her body.

According to a report by the St. Louis Post-Dispatch, officers went to the house to look for Joseph because one survivor from the Southwest Missouri murders identified him as the gunman.

Joseph Aldridge's body was later discovered with a self-inflicted gunshot wound inside his pickup truck parked just outside the gate to Warren Barnes' goat ranch in Summersville, said authorities.

According to Sigman, the gunman of the Southwest Missouri murders had a minor criminal history.

The Southwest Missouri murders occurred in a rural area of Missouri, thinly populated and near the Mark Twain National Forest. According to The Christian Post, the Division of Drug and Crime Control of Missouri is handling the case as well. However, officials denied any involvement of drugs in the crime.