An 18-year-old Boone man died in an accident on Interstate 35 Tuesday morning when his friend lost control of his vehicle.

Tyler Anderson was a passenger in a 1988 Dodge pickup truck, driven by 17-year-old Chad Chelsvig of Story City.

Chelsvig was merging onto Interstate 35 at about 9:45 a.m. when he lost control of the truck. He drove into the path of a semi tractor-trailer driven by 46-year-old Gary Raisch of Alden. The collision sent the semi cab over a concrete embankment, and the cab burst into flames, Iowa State Patrol officials said.

The semi skidded 15 feet across the top of a cement retaining wall, before it fell about 30 feet to Highway 30, hanging by just the rear wheels.

A passerby was able to drag Raisch from the semi-cab before the cab burst into flames, State Patrol officials said.

Story County Sheriff’s officials said once the tractor-trailer was lifted onto the retaining wall, the pickup truck was shot out from underneath the tractor-trailer. The pickup truck zipped back across both lanes of traffic, clipped the end of the wall, and rolled to a stop in a patch of grass on the opposite end of the overpass.

Anderson was pronounced dead on the scene.

Chelsvig and Raisch were both transported by emergency personnel to Mary Greeley Medical Center. Chelsvig was in fair condition Tuesday night, while Raisch was still listed in critical condition.

Eastbound traffic on Highway 30 and northbound traffic on Interstate 35 were halted for several hours while emergency vehicles and cleanup crews removed debris from the scene. Southbound traffic on Interstate 35 was also halted for a short time.

The accident is still under investigation by the Story County Sheriff’s Office.

– C.R. Cooper