Hamilton EMS platoon chief Jim Summers told CBC News that the incident happened on Imperial St., near Sherman Avenue North and Burlington Street East.
Paramedics reached the scene at 1:45 p.m.
Summers said that a piece of steel fell on the boy and crushed his head.
The boy’s father was with him at the time of the incident. It is not immediately clear why they were in the building where the incident occurred.
The boy was taken to Hamilton General Hospital, where he was pronounced dead.
Hamilton police say the boy's death is being investigated by both the coroner and the Ministry of Labour.