A boy was hospitalized Thursday in “grave condition” after he fell three stories from the roof of a Highland Park building where he was working, Pittsburgh police said.

The boy suffered a “serious head injury” after he fell from the building in the 5800 block of Bryant Street around 10:30 a.m., Eliza Durham, a police spokeswoman, said.

Police did not provide the boy’s name or age, identifying him only as a “juvenile male.”

Police said the victim was “doing roofing work at a construction site” at the time of the fall. They did not elaborate.

First responders rushed the boy to an area hospital.

The police bureau’s violent crime unit responded to the scene, which Durham called “typical for this type of incident.”

An Occupational Safety and Health Administration spokesman said Thursday that the federal agency is investigating.

The spokesman declined further comment.