Lt. Jerry Stanley of the Roussillon Police said a charter-type bus that was turning collided with the boy.
Police are still trying to piece together exactly what happened.
"It's an ongoing thing. [The] vehicles have to be taken to have [further testing]. There's witnesses that have to be met," he said.
The teen was wearing a helmet at the time, police said.
The driver of the bus, who was alone in the vehicle at the time, was treated for shock.