HINESVILLE, Ga. (WSAV) – Authorities have released the autopsy results of twin 3-year-old girls who were found dead inside a car in Hinesville Sunday afternoon.

According to Liberty County Coroner Reginald Pierce, Raelynn and Payton Keyes died of heatstroke. Their deaths have been ruled accidental.

Pierce said these are the preliminary autopsy results; a final report is pending.

Raelynn and Payton are the 45th and 46th children to die in hot cars this year.

According to the Hinesville Police Department, investigators are still working to establish a timeline of events on Sunday when the Keyes girls were found dead.

Hinesville PD says officers were called to a home on the 200 block of Augusta Way in the Griffin Park subdivision shortly after 1:30 p.m.

Earlier in the morning, a caregiver, now identified as a foster parent, could not locate the children inside the home after searching for them. The department said the foster parent searched the backyard and surrounding area in the neighborhood before returning to home to search again.

“It was during this second search that the children were found unresponsive inside a vehicle parked in the home’s backyard,” Hinesville PD stated.

Detectives told News 3 the foster parent then made the call to police.

“This is actually not the home of the caregiver or the children, this is someplace they come from time to time and do stay for extended periods of time and they were here visiting when this unfortunate tragedy took place,” Capt. Tracey Howard with the Hinesville Police Department added.

Authorities say the girls were staying with two caregivers and two of their other siblings.

Neighbors like Onesha Forrest are still reeling from the news.

“I wouldn’t know what to do if something like that happened to me. I’d probably lose my mind,” she said. Forrest, whose daughter is the same age, said she knows firsthand how curious kids can be.

“Sad to say, but always keep an eye on your child,” she added. “At the end of the day, it’s your responsibility to make sure they’re safe.”

Detectives say it’s still unclear how the children got inside of the car. Hinesville Police and the Georgia Bureau of Investigation continue to investigate.

Hinesville Police responded Sunday afternoon (Lewis Levine, Coastal News Service)

Contributions to this report made by Lewis Levine, Coastal News Service