California wildfire rages unchecked, threatens homes, shuts interstate
Smoke rises as the large delta fire spreads along Shasta County in California, U.S., September 5, 2018 in this picture obtained on September 6, 2018 from a social media video. CALIFORNIA HIGHWAY PATROL/via REUTERS

A wildfire burned unchecked early on Friday in northern California, threatening homes and shutting down an interstate highway where motorists had to race from their vehicles.

The Delta Fire has already scorched 22,000 acres (8,903 hectares) since it began on Wednesday in a Shasta-Trinity National Forest canyon along the Sacramento River, about 250 miles (402 km) north of San Francisco, the California Interagency Incident Management Team said in an advisory.

As of Thursday, firefighters had been unable to contain the blaze, said Brandon Vaccaro, a spokesman for the Delta fire command team, but a gradual rise in humidity is forecast, which could help slow the fire’s growth.

A stretch of Interstate 5 remained closed on Friday after the fire came near the highway. Motorists were forced to flee on foot on Wednesday before flames engulfed their cars and trucks, local media reported and fire officials said.

The fire was threatening about 150 homes and other buildings in the sparsely populated region. About 300 people were under mandatory evacuation orders, Vaccaro said on Thursday.

Farther north, an evacuation warning was in effect for the town of Dunsmuir, advising some 1,600 residents to be ready to flee at a moment’s notice.

The blaze was near the site of the Carr fire, which killed eight people and incinerated hundreds of dwellings in and around the town of Redding this summer, becoming one of California’s most destructive wildfires on record. No casualties have been reported from the Delta Fire.

The blaze has raged with the same intensity seen in several wildfires in recent months. Fueled by drought-ravaged pine forests thick with dead and dying timber, flames spread quickly, leaping from tree-top to tree-top and hurling showers of embers into more dried-out vegetation.

The Delta fire was one of about 15 blazes burning across California this week. Three times more ground has burned in California so far this year than at the same point in 2017, which ranks as one of the most destructive seasons on record.

Additional reporting by Brendan O'Brien in Milwaukee