An Alabama mom has been charged with murder in connection with the death of her infant son after he was left in a car overnight, police said.

Elizabeth Case, 36, was arrested in Athens, Ala. Saturday and was held without bond. It wasn’t immediately clear if she had a lawyer.

Police say Elizabeth Case “is a known drug user” and was out on bond in connection to first-degree robbery. Limestone County sheriff’s deputies said Case left home with the 13-month-old boy Friday evening to go “dumpster diving.” They said she left the child in the car when she returned home around 5:40 a.m. Saturday.