SPRINGVILLE -- A pilot and firefighter were killed Wednesday when their California Department of Forestry and Fire Protection plane crashed as they worked to battle a blaze in remote Tulare County foothills, authorities said.

The crash of the OV-10 airtactical plane sparked a three-acre wildfire near where firefighters battled the other blaze in the Mountain Home Demonstration State Forest, about 170 miles north of Los Angeles, said CDF spokeswoman Becki Redwine.

The plane, which was surveilling the fire for ground crews, had no communication just before the crash around 10:25 a.m., she said.

The victims were identified as George Willett, 52, a Hanford pilot contracted to help battle the fire, and CDF Battalion Chief Robert Paul Stone, 36, of Visalia.

More than 75 CDF and sheriff's deputies responded to the scene, but the rough terrain made it hard to reach the crash, Redwine said.

The original three-acre fire -- thought to have been caused by a campfire -- was fully contained.

The National Transportation Safety Board was investigating the crash.