It tore through canyons and flew over ridges in every direction with astonishing speed, sending flames 25 meters skyward and forcing tens of thousands to flee their homes.

The Southern California wildfire that began as a small midmorning patch of flame next to Interstate 15 in the Cajon Pass had by Tuesday's end turned into a 72-square-kilometer monster that had burned an untold number of homes.

"This moved so fast," said Darren Dalton, 51, who along with his wife and son had to get out of his house in Wrightwood, a mountain town of 4,500 popular with skiers in winter. "It went from 'have you heard there's a fire?' to 'mandatory evacuation' before you could take it all in. This is a tight little community up here. Always in rally mode. Suddenly it's a ghost town."

Hundreds of cars packed with residents, belongings and animals left the town. The air around the blaze was filled with smoke. The sound of explosions - possibly from ammunition stored in homes - could be heard in the distance.

Shannon Anderson of Blue Mountain Farms horse ranch in Phelan had to load up and evacuate 40 horses as the fire approached. "It's raining ash," Anderson said, breathing hard.

They were among more than 82,000 people from over 34,000 homes were under evacuation orders, said Eric Sherwin of the San Bernardino County Fire Department.

Devouring ranchlands 100 kilometers east of Los Angeles, the blaze surged west to the Los Angeles County line and east to the Mojave Desert in the east. The damages were likely to be vast and serious once they could be properly measured.

Sherwin confirmed on Tuesday night that it had burned at least a dozen buildings, some of them homes. He said he had seen all kinds of things burn, including the Summit Inn, a historic diner near I-15, he said.

"I'm looking up here and I'm seeing buses, I'm seeing outbuildings, I'm seeing houses," he said.

It was among several large fires burning up and down California, from Shasta County in the far north to Camp Pendleton Marine base in San Diego County. It came after several steady weeks of major fires around the state, even though the full force of fire season has yet to arrive.