Authorities say a mother in Louisiana will face negligent-homicide charges after her two small children died in a house fire while she was getting her hair styled.

Investigators say an arrest warrant was issued Tuesday for a woman from Bastrop who allegedly left her 3-year-old son and 4-year-old daughter unattended for hours.

Louisiana State Fire Marshal Deputy Chief Brant Thompson said the 21-year-old mother will be arrested after her release from a Shreveport medical facility where she's on a 72-hour hold by the Morehouse Parish Coroner's Office. Thompson says she was transported there after locking herself inside her vehicle.

Investigators say they are still piecing together findings about the fire that killed the children.