A fast-moving vegetation fire burning along both sides of Highway 166 east of Santa Maria had blackened an estimated 12,400 acres by Saturday morning.

Containment was listed at 5%.

What started as a series a small fires shortly before 2 p.m. quickly turned into a two-front conflagration straddling the rural highway, according to Flemming Bertelsen, a public information officer for Los Padres National Forest.

One head of what has been dubbed the Gifford Fire was moving northeast from Highway 166 toward the recent Madre Fire burn scar, while a second head was pushing south toward the Sierra Madre range, Bertelsen told Noozhawk.

The fires possibly were sparked by a motorist driving on a metal rim after a flat tire, according to the California Highway Patrol.

One of the original blazes broke out about 26 miles east of Highway 101, a second about 33 miles east, and a third and largest about 36 miles east, the CHP said.

Evacuations were ordered for the area north of Sierra Madre Road, south of Highway 166, west of Cottonwood Canyon Road, and east of the Willow Springs Trailhead, according to the Santa Barbara County Office of Emergency Management.

Evacuations also were ordered for areas north of Highway 166 in San Luis Obispo County.

U.S. Forest Service crews were battling the blaze, with assistance from firefighters from Santa Barbara County, San Luis Obispo County, and the Chumash Reservation.

A fleet of helicopters and fixed-wing aircraft were aiding the firefight from the skies, and two VLATs – Very Large Air Tankers – were on order and expected to arrive on scene at about 7 p.m., Bertelsen said.

Highway 166 was closed down at Highway 101 on the west and New Cuyama on the east, the CHP said.

This is the second significant fire to force the closure of Highway 166 this summer. After sparking July 2, the Madre Fire burned more than 80,000 acres north of the highway which was closed for a week.

Check back with Noozhawk for updates to this story.