TUCSON, Ariz. — Tucson Police Department’s child physical abuse unit is investigating the death of a 7-year-old boy who was found in the bottom of a family pool.

The boy’s mother called 911 on Thursday to report her son had gone missing about 30 minutes prior. When officers arrived, they skimmed through the “dirty, murky and green” water in the pool and found the boy.

The pulled him out and initiated CPR until paramedics arrived, but the boy died from his injuries.

Sgt. Pete Dugan says there was no barrier between the house and the pool.