The girlfriend of a man accused of running down and killing a developmentally disabled man after a Fourth of July dispute has been reported missing, authorities said.

Newton County deputies said Kendra Browning is likely with her boyfriend Joshua Anderson, and her family believes she could be in danger, Channel 2 Action News reported.

Authorities have been searching for Anderson since Thursday, when he allegedly ran over 20-year-old Kevin Marshall on a residential street near Covington before speeding off. Marshall later died.

RELATED: Developmentally disabled man run over, killed after July 4 fight in Newton County

Witnesses said Anderson and Marshall got into a fight at Browning’s home on North Lake Drive. Bystanders broke up the scuffle, but as Marshall walked home, Anderson allegedly got into his Toyota pickup truck, sped down the road and hit him, the news station reported.

Marshall’s mother told the news station her son had the mental capacity of a 13-year-old.

“He wasn't doing anything. He wasn't doing nothing,” Robbie Marshall said. “He was such a sweet boy. He wouldn't harm nobody. ... This man got in his truck and he ran over my son and he killed him.”

Police say??Joshua Anderson mowed down Kevin Marshall, 20, after an argument on the Fourth of July.??

Deputies said Browning likely left with Anderson willingly, but it’s unclear if she knew he was wanted on a murder charge after the hit-and-run.

Anderson is wanted on charges of malice murder, felony murder, aggravated assault, first-degree vehicular homicide, hit-and-run and reckless driving. Police said he should be considered armed and dangerous.

The vehicle Anderson was last seen driving, a gray 2001 Toyota Tacoma, was found in a wooded area near his house, but authorities said Monday that Anderson is still on the run. He may now be traveling in a 2005 Toyota Highlander.

Anyone who knows the whereabouts of Anderson or Browning is asked to call Newton County deputies at 770-784-2100 or Crime Stoppers at 404-577-8477.