PHOENIX - A 3-year-old boy has died a day after being left in a hot car for several hours while his mother and a family friend were in church for a choir practice, police said Monday.

Officer James Holmes says the family friend had taken the boy and other children to a church where the friend and the child's mother had choir practice late Saturday morning. The mother had arrived earlier.

Hayden Nelson was not discovered missing for three hours, following the end of choir practice at 2 p.m. By then, temperatures had reached the high 90s, and the child wasn't breathing when he was found in the vehicle, Holmes said.

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"It's obvious that the 27-year-old forgot that the child was in the car," Holmes said, referring to the family friend. "She was in a hurry. She had something that she had to do, and she didn't take a minute to make sure."

The boy was hospitalized in extremely critical condition but died Sunday afternoon.

Police did not immediately identify the friend. The case will be referred to prosecutors to decide whether to press charges, Holmes said.

"You cannot imagine what this lady is going through right now, what this family is going through," Holmes said of the friend.