The Mesa Police Department is investigating what led to the drowning of a 4-year-old Saturday afternoon.
Mesa fire crews arrived on scene shortly before noon to the area of University and Val Vista Drives.
Mesa police have identified the boy as 4-year-old Richard Wilcken.
According to fire officials, the child was discovered in a pool after the family was unable to locate him for an unknown period of time. Mesa fire say the pool was not fenced.
They believe the child climbed out a window and proceeded to the pool area. The father was eventually able to see the child in the pool, despite the pool being very murky.
Crews provided advanced life support to the boy after arriving on scene, and was transferred to a pediatric hospital where he was later pronounced deceased.