The Mississippi Bureau of Investigation and the Panola County Sheriff's Office were seeking phone records and witnesses to find out who fatally lit a teenage girl on fire.
A passerby called the sheriff's office about the burning car along Herron Road, near Highway 51, Saturday night.
Responders took 19-year-old Jessica Chambers to the Regional Medical Center in Memphis, where she died.
Jessica's father said his daughter tried to tell responders who killed her.
The sheriff's office previously told WREG it's possible Jessica had plans with two people that night, although Assistant District Attorney Jay Hale said there are no clear-cut suspects at this time.
He said her autopsy was underway Monday.
WREG met with Lisa Chambers, Jessica's mother, Monday at a funeral home, after she finalized plans for her daughter's burial.
Chambers said her daughter lived with her, and Jessica planned to go get her car cleaned Saturday evening. She spoke with her daughter on the phone around 6:48 p.m., and Jessica said she was going to get a bite to eat.
"[She] said 'Bye, I love you, Mama. See you in a little while.' Next time I seen her, she was in the Med," Chambers said.
Chambers wants justice for her daughter, who she said was acting normally Saturday. She said her daughter had a job at a department store, cheered in high school, and didn't currently have a boyfriend.
"God's punishment is going to be far more worse than anything that we can do," Chambers said about her daughter's killer.
Hale said it was possible Jessica's murderer could face life in prison without parole, or even the death penalty.
Jessica's family confirmed her visitation will be at Wells Funeral Home from 5 to 8 p.m. Friday. Her funeral is at the same location at 2 p.m. Saturday.
This story was originally published by WREG in Mississippi, and was distributed by the CNN Wire.