CHICAGO (CBS) — The Illinois Department of Children and Family Services was investigating Monday after a 7-month-old baby died after being left alone in a bathtub in the South Shore neighborhood.

Police said just after 1 p.m. Sunday, officers were called to the 7500 block of South Coles Avenue and found Fire Department crews already on the scene. They were performing CPR on the boy, police said.

The boy’s mother told police that she had put him in the bathtub and left, only to find him unresponsive upon returning 10 minutes later, police said.

The boy was taken to the University of Chicago’s Comer Children’s Hospital, where he was pronounced dead at 1:55 p.m., police said.

He was identified by the Cook County Medical Examiner’s office as Lendel Collins.

The DCFS said it is investigating Lendel’s death as a drowning incident. Area South detectives are conducting a death investigation.