A fast-moving fire in Northern California destroyed 50 homes and forced 10,000 people out of their residences, authorities said on Wednesday.

The 49,000-acre (19,845-hectare) blaze north of Sacramento in Northern California jumped a fire line, forcing the evacuation of at least 10,000 residents in Paradise, 90 miles (162 kilometers) north of Sacramento and caused the worst damage in the rural community, officials said.

Officials said the greatest damage was in the rural town of Concow, where the blaze had jumped the fire line Monday night, but other nearby communities are also threatened.

The fire as of this morning was contained at 40 percent, but evacuations were still in place for people living in 3,800 threatened homes, said Daniel Berlant, a spokesman for the California Department of Forestry and Fire Protection.

"We saw active fire Tuesday night, with the fire growing about 2,000 acres (810 hectares)," Berlant said. "It was nothing compared to how bad it was Monday night, but we still have a few days of bad conditions ahead of us until we catch a break."

"There's just no predicting how things will go," said Wes Cochran, a spokesman for the state forestry department.

Meanwhile, firefighters make progress against the blazes in Goleta and Big Sur in the region.

In Goleta, as of 6 a.m. local time on Wednesday, the 9,700-acre (7800-hectare) fire was declared 55-percent contained, though officials could not predict when it would be fully encircled.