NORTHSTATE, California — Emergency crews battling the massive park fire were tested by strong wind gusts Saturday evening into Sunday night, but were able to reinforce containment lines, officials said in an update Sunday.

“Today, crews are working to ensure the fire remains within the existing perimeter by increasing cleanup efforts, removing hazardous trees, conducting tactical patrols, mitigating hot spots and ensuring areas are safe for repopulation,” officials said.

As of Sunday, the Park Fire has burned 429,267 acres in Butte, Tehama, Plumas and Shasta counties and is 51% contained. The fire is currently the fourth largest fire in California history.

The strong wind during the night increased the risk of local fires, but the emergency services were able to quickly fight the few fires that occurred overnight and thus prevent them from spreading.

Officials added that due to the strong winds overnight and the humidity, there is a possibility that there are more hot spots that have not yet been discovered. Firefighters have been urged to be on the lookout for such incidents and respond vigorously to extinguish any hot spots that may arise.

The mild weather and higher humidity put firefighters in a “good position” to continue containing the fire front on Sunday, officials said.

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The park fire began July 24 in Upper Bidwell Park, northeast of Chico, and was man-made, authorities said. Investigators said Ronnie Stout, 42, of Chico, was allegedly seen pushing a burning car into a ravine near Alligator Hole, where the fire first started. Stout faces several charges.

Many residents were able to return to their communities after evacuation orders were lifted, but some are returning to a pile of rubble where their homes once stood. The Park Fire destroyed 641 buildings and damaged dozens more.

Many evacuation orders have been lifted or downgraded as the park fire is better contained and areas reopen. Some parts of Lassen Volcanic National Park reopened Saturday after evacuations were lifted.

However, evacuation orders and warnings are still in effect for areas still threatened by the fire. For the most up-to-date evacuation information, visit View the evacuation zone map here.

Road closures

Tehama and Shasta Counties

• Highway 172 between Mineral and Hole in The Ground Campground
• Highway 89 between Highway 36 and Summit Lake

Cal Fire officials are asking the public to be cautious when returning home as firefighters are still in the area.