BENTON CITY -- A fiery crash on Interstate 82 near Benton City caused by inattention killed a 32-year-old father of two from Georgia, troopers said.

The three-vehicle collision Wednesday morning started when a tow truck driver slammed into a slow-moving pilot car traveling behind a semi-truck carrying an oversized load.

The impact sent the car into the back of the semi-truck, where it got stuck underneath the trailer that was carrying a giant transformer.

The car then burst into flames, killing Stephen L. Roberts, of Doerun, Ga.

"It's very, very sad," said Shelby Costello, owner of Costello Flag Car Service. Costello was the lead escort and had been traveling with Roberts for about 15 days. "He was a nice young man."

The trip started in South Boston, Va., and they were just hours away from their final destination in Seattle.

Costello said he and the semi-truck driver, Henry Dortmans, tried to get Roberts out of the car, but by the time they got to him, the car was engulfed in flames.

"We couldn't get him out," he said.

Costello estimates Dortmans was going about 25 mph as they were climbing the hill just past Yakitat Road around 10:15 a.m. They were about two miles west of Benton City.

"We weren't going very fast at all. We were in the right lane, just crawling up the hill," he said.

Roberts was following behind in the 2004 Ford Crown Victoria. The pilot car had a large sign on top and flashing yellow lights.

"When (Dortmans) hollered up to me that he had been rear-ended, I looked up in my mirrors and just saw smoke," Costello said. "I hollered to the other driver and he didn't respond. I immediately backed up to the load."

Timothy Haley, 25, of Outlook, was driving the 2002 International tow truck that hit Roberts' car. Costello said Haley got to Roberts' car first with a fire extinguisher and tried to put out the flames.

"He did not say anything about the accident. He was just yelling 'No! No! No!' and stuff like that," Costello said.

"We don't know if there was anything in the left lane beside him and he couldn't get out to go around us or he was distracted in the truck doing something. It's quite obvious he wasn't paying attention. Why he was not paying attention, I could not tell you."

Another trucker, Aaron Meyers, said he was heading east on I-82 when he saw the wreck.

"The guy in the tow truck -- he didn't even hit his brakes," said Meyers, who called 911 and reported the crash.

Meyers, of Fife, drives for Coastal Pacific, a food distributor for the military, and was on his way to an off-site sale in Pendleton. He said had stopped for a break at the Prosser rest stop and left there about 10 a.m.

"The pilot car was about 15 feet behind the trailer. The (collision) pushed it up into the trailer and crushed it like a sardine," he said. "It was on fire within three seconds of the collision."

Meyers said the semi-truck was getting to the top of the hill, there were no other vehicles around the truck, and Haley should have had an unobstructed view of the pilot car.

"I felt just complete sorrow the moment that I saw the accident," he said. "It was kind of like watching a building on fire and you're standing right there and you can't do nothing to help. ... There's nothing you can do and you're just completely, utterly helpless.

"It almost felt like it was in slow motion," he added. "I really feel bad for the person."

Washington State Patrol Sgt. Jody Metz said the crash still is under investigation, but investigators know that drugs or alcohol were not factors in the collision. Haley also was "not on a cellphone" at the time, but they're still trying to figure out what caused him to be distracted, she said.

Both westbound lanes of I-82 were closed for a short time after the crash because fire crews had to extinguish the flames. A single lane remained closed until about 3:30 p.m. so troopers could complete the investigation.

Haley suffered minor injuries and was treated at Kadlec Regional Medical Center in Richland.

Dortmans, 58, and his wife, Linda, 55, of Carrizo Springs, Texas, were not hurt.

Metz said motorists need to remember to pay attention when they're on the road and trying to look ahead as far as they can so they have time to react if there's a disabled car, slow-moving vehicle or a pedestrian on the highway.

"When you're going to drive somewhere, pay attention to what you're doing and anticipate some things," she said.