SAN ANTONIO – San Antonio police said a driver was unharmed after his truck exploded on an access road overnight.

The fire was reported just after 10 p.m. Wednesday in the 7400 block of Highway 90 West.

Police said they believe the truck was involved in racing two other vehicles before the fire occurred.

The driver, who did manage to get out of the vehicle safely before it exploded, had boosted his engine with nitrous oxide which caused the explosion, police said.

Police said the truck's roof blew off, landing roughly 75 feet away.

There is no word on any arrests as a result of the racing.

The investigation is ongoing.