A Louisiana woman has been arrested after her 2-year-old niece died in a hot car where she had been left for about six hours.

The St. Charles Parish Sheriff’s Office said Wednesday that Avril Sanabria died Oct. 4.

Lezly Sanabria, 48, was arrested Tuesday on negligent homicide charges, The New Orleans Advocate/The Times-Picayune reported. She’s being held at the Nelson Coleman Correctional Center. Bond has not been set. It wasn’t clear if she has an attorney.

The sheriff’s office said the toddler went shopping with her aunt and grandmother. When they got home around 1:30 p.m., the grandmother went to her house on the property and Sanabria and another person unloaded the car before going inside her home.

Lezly Sanabria told deputies she thought Avril had gone with her grandmother. About six hours later, Sanabria went back to her vehicle and found the girl still buckled in her car seat. The child was unconscious and not breathing.

The temperature that day reached as high as 97 degrees outside the car, the Sheriff’s Office said. Inside the car, the temperature could have reached 125 degrees to 140 degrees within 10 to 15 minutes, authorities said.