At 5:12 a.m. Saturday, Rural/Metro firefighters responded to multiple calls of a fire in the area of Tierra Mesa Estates off County 14th St.

The callers said they heard a loud boom, sounding like an explosion.

Firefighters found a semi truck with a trailer engulfed in flames.

Rural/Metro said the semi truck had been parked there since around 3 p.m. Friday, and the trailer was empty because the owner of the vehicle had unloaded it.

No one was in the vehicle, and no one was injured.

There are homes nearby where the fire happened, but the flames did not spread.

The cause of the fire is under investigation.