A 4-year-old boy was found at 756 W. Sublette in Pocatello wearing only underwear, police said Monday.
Officers responded to a report of the boy, found him at his house, but no one was home.
The child was brought to the station and Child Protection was notified.
Officers were able to get in contact with the boy's grandmother, who was at work.
Police said they determined the child was left at home with a 17-year-old uncle, who assumed there was an adult at home when left to go to the gym and left the child unattended.
As of Monday morning, the grandmother was en route to pick up the boy.