Three big rigs catch fire in West Central Fresno

FRESNO, Calif. (KFSN) -- An investigator is working to figure out what sparked a fire that burned three big rigs in West Central Fresno.

It happened after 1:30 on Tuesday morning near Shields and Polk.

Fire crews arrived to find one semi engulfed in flames, a second partially burned, and a third rig with minor damage.

Firefighters were able to put the flames out quickly.

No one was in the semis, and no one was hurt.