Crash investigators believe Thursday's fiery, multivehicle accident on I-15 that claimed the life a Payson man and shut down a section of freeway for almost a day may have been prevented with a little patience.

A chain reaction collision involving eight vehicles likely started when a southbound belly dump truck had to stop abruptly to avoid hitting an aggressive driver who apparently darted out of the southbound exit-only lane near 9000 South, according to Utah Highway Patrol Lt. Verdi White II."That's the theory we're still going on," White said.

The man who died in the 8 a.m. accident has been identified.

Killed was:

Shawn M. Nilson, 37, Payson.

Miraculously, said White, there were no other serious injuries.

"We could have easily had a multifatal accident," he said.

When the belly dump truck slowed it was rear-ended by another southbound dump truck, which was subsequently rear-ended by a fuel-laden tanker truck and another heavy truck driven by Nil-son, White said.

Four other passenger vehicles were also involved in the collision, which stretched tangled wreckage across the freeway and a tower of smoke and fire into the air when the fuel tanker ignited.

Investigators are hoping to find the driver of the car that witnesses say pulled in front of the first dump truck so they can glean more information about the accident.

A team of highway workers was enlisted to repair sections of the interstate that were seriously damaged by the accident and the subsequent fuel tanker explosion.

Crews had to sweep debris from the accident, repair damage and replace a section of asphalt before both sides of the roadway were deemed passable, said Utah Department of Transportation spokesman Mark Frederickson.

Both north and southbound lanes of I-15 near 90000 South were opened by 6:30 a.m. Friday, early enough to ease traffic for most commuters.

Although Thursday's accident is being called one of the most serious incidents on a section of I-15 impacted by construction, highway officials are pleased with the timely manner rescue and repair workers were able to access the crash site.

"There were not problems whatsoever in responding," said White, who said construction access roads provided easy entry onto the freeway.

Nilson - who was married to his wife, Sandra, just a few weeks ago - was remembered by his brother-in-law, Tim Durrant, as a "standard Utah guy" who enjoyed the outdoors.

He was the father of five children from a previous marriage and employed by Savage Industries.