A 9-year-old boy was struck and killed by a yellow school bus in Brooklyn Friday morning, according to police.

The boy was crossing the street at Lee Avenue and Lorimer Street in Williamsburg when he was hit by the bus around 8:20 a.m., police said.

First responders found the boy unconscious and unresponsive with severe injuries to his head and body.

He was declared dead at the scene.

The bus driver, a 49-year-old man, initially fled but returned once he realized he’d hit someone, sources told The Post.

No charges have been filed at this time.

This is a developing story. Please check back for updates.