DPS reports indicate that one of the commercial tractor trailers owned by Schneider National Inc. was traveling west bound, up a hill when it was rear-ended by another commercial tractor trailer traveling at a higher rate of speed.  As a result of  the impact the fuel tanks on one of the tractor-trailers ruptured and ignited a fire.  The trailer of the Schneider National truck was consumed along with the tractor trailer that ran into the back of the Schneider truck.

Hazardous Materials Technicians from DPS and the Flagstaff Fire Department were called to the scene because the Schneider National trailer contained a load of hazardous materials which included lighter fluid and 300 pounds of an unknown corrosive material.

I-40 was closed in both directions. At 7:19 a.m. I-40 was reopened to westbound traffic after the fire had been extinguished and experts on scene determined the hazardous materials did not pose a threat to air quality.

The driver and co-driver of the first vehicle were not injured in the collision. The driver and co-driver of the second vehicle were both transported to the Flagstaff Medical Center where they were treated for non life threatening injuries.

DPS investigators believe that driver fatigue may have been a factor in this accident.

All lanes of I-40 re-opened at about 11 a.m.