By The Canadian Press

HINTON, Alta. - Joel Chell sat in stunned horror, watching in his rear-view mirror as a stolen minivan that had just whizzed by him on the wrong side of an Alberta highway blew apart after slamming head-on into a pickup truck on the road behind him.

The 50-year-old felt slightly sick as a ball of orange flames bloomed through the wrecked remains of the two vehicles. It was like something on a television show.

"Everything caught fire and burned in what must have been a minute or less," Chell said in an interview Friday.

A provincial police review agency is investigating the crash, which happened late Thursday afternoon near the community of Hinton, Alta., west of Edmonton.

Mounties were chasing the van when it happened.

Both the 21-year-old driver of the fleeing vehicle and the innocent driver of the pickup were killed instantly.

Police were made aware of the minivan well to the west of Hinton when an off-duty RCMP officer reported seeing it being driven erratically, said Clifton Purvis, executive director of the Alberta Serious Incident Response Team, which is handling the investigation.

The driver refused to stop for an RCMP cruiser at the east gates of Jasper National Park. Police did not pursue the van at that point and instead informed officers in Hinton that the vehicle was headed their way on Highway 16.

The driver didn't stop for police in Hinton either and sped away as it entered the community with at least two cruisers in pursuit.

"It then began to travel eastbound in the westbound lanes of the highway that runs through the town of Hinton," Purvis said.

What happened next is still under investigation, but early reports suggest the van veered back into the proper lane, before again steering into the oncoming lanes of traffic, he said.

Drivers who saw the van coming at them were forced to get out of its way.

"I know that there are reports that numerous cars took evasive action to avoid a collision," Purvis said.

Chell, on his way back to Hinton after a business trip with his boss, narrowly missed being hit as his vehicle approached the top of a small hill just outside the community limits.

It was dusk and the van came speeding toward them in the wrong direction with its lights off. There was only a split second to react.

"I just sat there and 'poof,' they went past," said a still rattled Chell. "I heard a loud sound, almost like a balloon popping in the back seat. Looked in the rear-view mirror and saw junk flying everywhere in the centre of the median."

A shocked Chell pulled over and that's when he saw the flames.

"I thought, there's no way I want to go back there and even look ... I just went, 'that's going to be a terrible thing to look at.' I didn't want to sit there and watch it burn because it was too disturbing."

His relief at narrowly escaping a deadly collision soon mingled with sadness at the thought someone else had not been so lucky.

As many as three RCMP vehicles were driving on the proper direction on the highway, following the speeding vehicle, Chell said. He saw several more police vehicles heading to the scene as he drove back into town.

Purvis confirmed the vehicle was stolen, but would not say where it had been stolen from. He did suggest the fact it had been reported stolen may explain why the driver failed to stop for Mounties.

There were no passengers in either vehicle, Purvis said.

Efforts were still being made Friday to officially identify both men. Because no positive identification had been made, Purvis couldn't say whether the driver of the stolen vehicle was known to police.

ASIRT's job will be to examine the conduct of RCMP officers while questions about whether procedures on handling chases were properly followed will be looked at by an internal RCMP probe.

"After gathering all the facts, we will examine the conduct of the RCMP officers involved in this incident, and determine whether their actions were justified and lawful."

It's difficult to say just how many police vehicles may have been involved, he said.

"That will be one of the things we'll look at and determine when police vehicles became involved in the pursuit and what their roles were."

Investigators will speak to the RCMP officers, any other witnesses and police dispatchers.

And they also have a key piece of evidence to rely on - the RCMP vehicles involved were equipped with video recorders.

"We've secured that evidence so we have a very clear visual of what the police were looking at when they were involved in this situation," Purvis said.

Only three of the 47 cases involving police that the agency has investigated involved pursuits.

The review could take months as investigators wait for results of tests to determine whether drugs or alcohol may have been factors.

It's not the first time Chell has been driving on a highway and seen someone driving in the wrong direction. But he's never been this close to such a horrifying collision.

The significance of what he called a "surreal experience" only sank in when he got home Thursday evening and looked at his two teenaged sons, both of whom are just learning how to drive.

"I went and hugged my kids," he said.