A truck driver has died in a fiery crash on B.C.'s Highway 99 just south of the Massey Tunnel on Wednesday morning. 

Delta police say several witnesses attempted to free the trapped man from the truck, which was fully engulfed in flames. He was the lone occupant of the truck and his identity will not be released pending next of kin notification.

"We tried to get out there to do what we could to help him, but it was too late. There was loud bangs, tires were flying. It was time to step back," said witness Gary Edgar.

"We were yelling at him. We were pretty confident he was unconscious throughout all this, but there was no way to get him out."

Truck crash witness tried to save driver RAW0:36

The accident happened around 9 a.m. PT near the overpass for Highway 17A, also known as the Ladner Trunk overpass. Witnesses reported explosions after the southbound dump truck hit the highway median and burst into flames.

Google Maps: Highways 99 and 17A

Two vehicles in the northbound lanes were also damaged after being hit. The drivers of both vehicles were transported to hospital with non-life threatening injuries. The cause of the fire is still under investigation.

The highway was closed for most of the day and the evening rush hour traffic. 

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