A van was seen partially wedged inside of an RTD bus after a fiery crash in Boulder County Monday morning.

The Boulder County Sheriff's Office says a car, a bus and a semi-truck carrying a van were involved in the wreck, which happened near Arapahoe Avenue and 65th Street.

The van caught fire, and one person was pinned inside of a vehicle, the sheriff's office said. An employee with the company that owns the van says the victim was taken to the hospital with severe burns.CSP says the driver, a 25-year-old man, was sent to Boulder Community Health then flown to University Hospital.

Colorado State Patrol says a number of people were inside the bus at the time of the collision. Investigators say the semi was traveling on Arapahoe with the van behind it when it came to a complete stop.

CSP says the RTD bus driver, later identified as Richard Castle, 73, had plenty of room to avoid the crash, but nevertheless slammed into the van. He's been summoned for careless driving causing injury.

The third vehicle rear-ended the bus. No one was seriously injured, but some of the people inside may have been taken to the hospital with minor injuries.