The Charlton County Sheriff's Office has released new details about their investigation into the apparent double murder-suicide that happened at a home Tuesday near the Florida-Georgia line.

The police report states authorities responded to a call at 1418 St. Mary's River Bluff Road and found three people dead inside -- a boy and two women, identified as Caleb Logan Butts, 15, his mother Kimberly Gayle Butts, 39 and Jan Elizabeth Kirkland, 64, the mother of Kimberly and the grandmother of Caleb.

A preliminary investigation done by the Georgia Bureau of Investigation shows that Caleb died from multiple gunshot wounds and Jan died from a single gunshot wound and Kimberly died from a self-inflicted gunshot wound.

When authorities entered the residence, they said they smelled a strong odor of gas from the stove in the kitchen and found two of the back burners ignited. They also found one of the women dead from a gunshot wound to her head near the kitchen, and another woman and Caleb dead in the master bedroom. They said the woman also had a gunshot wound to her head and a pink semi-automatic handgun on her left shoulder. Caleb was laying next to her with multiple gunshot wounds to his chest.

The preliminary investigation indicates the incident was a double homicide-suicide, GBI says, but the person who fired the shots and then had a self-inflicted gunshot wound still needs to be confirmed by the medical examiner.

READ MORE >> GBI identifies teen boy, 2 women found dead at home near Florida-Georgia line