The Hokkaido prefectural police headquarters in Sapporo. Photo: Jiji Press
Around 10:00 am on Sunday, the boy's mother called for an ambulance reporting the accident.
According to the Hokkaido prefectural police department, the escalator where the accident occurred is located outside, connecting a parking lot with ski slopes.
It is shaped like a conveyor belt with no steps on the part where people stand.
The boy, Hinata Goto from Sapporo, Hokkaido's capital, fell near the exit of the escalator and his right arm became trapped in the belt's turning section, police and fire authorities said.
He was trapped for around 40 minutes before being taken to hospital unconscious, where he was pronounced dead.
