Within hours, dozens of houses were wiped out by a California wildfire that started at a thickly wooded place in the Sierra foothills, located 55 miles northeast of Sacramento.

The River Fire broke out close to Milk Ranch Road as Bear River Campground road at 2 in the afternoon. The area is located about three miles southeast of Placer County’s Colfax town.

By 7:30 p.m. on Wednesday, the fire already devoured 1, 400 acres due to high winds and arid conditions. The Cal Fire said the damage grew to 2, 400 acres by Thursday, as it completely damaged 50 structures and left damages to 30 others.

Threatened structures were at about 3, 400, half of them were located in the Colfax area. With this, evacuated residents in Placer and Nevada counties have surpassed 6, 000.

“Very surreal seeing the damage from the #RiverFire in Colfax off the 25000 block of Pine View Drive,” wrote ABC News reporter Lena Howland on Twitter. “Homes in every direction on the end of this road have been reduced to rubble, power lines down and we’re still seeing active flames.”

According to Car Fire, the flames crossed the Bear River and went on affecting Nevada County. It was crawling towards Highway 174 as of Wednesday evening.

The flames have covered the Bear River Campground in Placer County, according to the Nevada County Office of Emergency Services. It threatened locations east of Dog Bar Road.

University of Nevada’s department of physics professor of atmospheric sciences, Neil Lareau, said the fire ejected a deep smoke fume carrying heavy ash, SFGate reported.

“Some impressive fire behavior (and flames) visible as the #RiverFire gets established,” he wrote as he shared on Twitter an image showing the smoke.

With the windy conditions and low humidity levels, the fire is anticipated to keep on raging until Thursday. “Multiple firefighting aircraft from throughout the state are flying fire suppression missions as conditions allow,” Cal Fire said.