GALLMAN, Mississippi (CNN) -- A mother, stepfather and 7-year-old boy missing in Mississippi have been found dead, a sheriff said Tuesday.
The bodies of Atira Hill, Laterry Smith and Jaidon Hill, 7, were found overnight in a wooded area, said Copiah County Sheriff Harold Jones. They had been shot to death.
The family was last seen Friday traveling in a car. That vehicle was later found flipped and on fire.
Authorities have arrested 42-year-old Timothy Burns on suspicion of arson, Jones said. He is also being held for "investigative purposes" in connection to the killings, according to the sheriff.
It was not immediately clear whether Burns had retained representation. He was being held at the jail in Copiah County, southwest of Jackson.
"This happened to a 7-year-old child, and he did not need to have this visited upon him," the sheriff said about the youngest victim. "He had a very bright future."
An investigation is ongoing, but at this point, authorities believe Burns was driving the car, got into an accident and then set the vehicle on fire, Jones said.
It's not known yet whether the victims were in the car at the time of the accident. Nor is it known whether Burns and the victims had ties, though the sheriff believes they did not.
He said Burns led authorities to the bodies.
"We're investigating. This just happened," Jones said.
According to Hill's mother, Judith Hughes, Hill called early Saturday to say she and Jaidon were on their way to meet Smith's relatives to "take care of some business."
Hughes said she asked her daughter if everything was OK. She said it was.
The phone signal was weak, and the call dropped. Hughes tried calling back, but the call went straight to voice mail.
Hughes said Jaidon lived with her and that he was meant to spend the weekend with his mother.
After the family's car was found flipped, Hughes said she went to the home where Hill and Smith are believed to have lived. It was empty, she said.
According to her mother, Hill worked as a nurse assistant at the University of Mississippi Medical Center.
-- CNN's Dana Ford and Meridith Edwards contributed to this report.
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