13,000 people ordered to evacuate as devastating wildfire rages across Northern California

Some 13,000 people in Northern California have been ordered to evacuate from their homes as an enormous wildfire rips through the area, amid a sweltering heatwave on the US west coast .

Almost 1,500 emergency personnel are involved with operations at the scene of the Thompson Fire in Oroville, in Butte County – which has so far consumed more than 4.7 square miles since it began on Tuesday morning .

Firefighters lined roads to keep flames from reaching homes as helicopters dropped water as the fire continued to grow on Wednesday. By 9am local time the blaze was still zero percent contained according to the California Department of Forestry and Fire Protection (Cal Fire).

Four firefighters were injured while responding to the blaze, though there had been no civilian injuries or casualties, the department said.

Dramatic pictures from the scene showed houses, vehicles and nearby woodland completely engulfed in yellow and orange flames.

The city of Oroville, which has a population of about 20,000 people, declared a state of emergency Tuesday night. Several homes have been destroyed, KCRA-TV reported Wednesday, with two evacuation centers set up in Butte County.

Other pictures showed night flying helicopters dousing the flames as they ripped through forested areas.

The fire’s cause is being investigated. Red flag warnings for critical fire weather conditions, including gusty northerly winds and low humidity levels, were in effect when it erupted.

The warnings were expected to remain in effect until 8pm PT on Wednesday, said Garret Sjolund, the Butte County unit chief for the California Department of Forestry and Fire Protection.

“The conditions out there that are in our county this summer are much different than we’ve experienced the last two summers,” Sjolund said in an online briefing, according to the Associated Press . “The fuels are very dense, brush is dry. And as you can see, any wind will, move a fire out very quickly.”

More high temperatures above 100F were forecast Wednesday, the National Weather Service said. Hot conditions were expected to continue into next week.

Authorities warned of full legal consequences for any illegal use of fireworks during the Fourth of July holiday on Thursday.

“Don’t be an idiot, cause a fire and create more problems for us,” said Butte County Sheriff Kory L Honea. ”No one in the community is going to want that. And we certainly don’t want this."

Evacuation operations continue.

California Governor Gavin Newsom’s office announced late on Tuesday that federal funding had been approved to help with firefighting efforts. Earlier this week Governor Newsom activated the State Operations Center to coordinate the response, dispatch mutual aid and support communities as they respond to threats of wildfire and excessive heat.

More than a dozen other fires, most of them small, were active in California, according to Cal Fire.