Warren Gastelum, 27, was arrested  Dec. 12, after a 2-year-old girl was found unresponsive in a bathtub while under his care.

Kamia Baptisto died from her injuries on Dec. 17. Additional charges are now pending against Gastelum, who was arrested on one count of child abuse two days after the incident, Tucson police said in a news release.

Shortly before 11 p.m. on Dec. 10, Tucson firefighters called for police to assist with a near-drowning at an apartment, located at 1700 West Prince Road, near Romero Road, according to a Dec. 12 Tucson police news release.

Paramedics found Baptisto unresponsive inside the apartment and immediately transported her to a local hospital with life-threatening injuries.

Officers spoke with Baptisto's caretaker, identified as Gastelum, who was the boyfriend of the child's mother. He told police that he was alone that night with four kids under the age of eight while his girlfriend was at work, and put the 2-year-old in the bathtub before stepping away for a few minutes. He said that when he returned, she was unresponsive and he called 911, according to the release.

Detectives with the child abuse unit spoke to the girl's doctor, who said that her injuries weren't consistent with drowning or a fall in the bathtub, the release said.