While firefighters are making progress on the northern California Mill Fire, the nearby Mountain Fire has picked up. 

The Mill Fire has spread over 4,263 acres and is 40% contained. 

The fire's full containment is expected in a little over a week, with personnel strengthening control lines and providing structure defense throughout the area.

Hundreds of structures have been threatened, and 88 single structures were destroyed.

CALIFORNIA WILDFIRE: SHERIFF CONFIRMS 2 FOUND DEAD DUE TO MILL FIRE

There have been three civilian injuries and two fatalities. 

Two women, ages 66 and 73, were found dead in the city limits of Weed, according to the Siskiyou County Sheriff's Office.

"Critical fuel moistures are a concern as the weather gets warmer and dryer. The fire is not anticipated to spread," Cal Fire wrote in a Monday update. 

There have been 559 people evacuated, but the sheriff has lifted some evacuation orders and warnings.

CALIFORNIA WILDFIRE SETS HOMES ABLAZE, FORCES EVACUATIONS

"We understand that everyone would like to get home, we ask for patience as the first responders continue to make progress and ensure the evacuated area is safe for your return," the office wrote on Facebook.

The Mountain Fire has continued to grow, with more resources arriving to fight the wildfire. 

The fire has spread over 10,338 acres and is 10% contained,

While there have been no injuries or deaths, more than 330 people have been evacuated in response to the blaze.

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The weather over the burn area is dry. 

"The fire is burning in steep, broken terrain in different types of vegetation," Cal Fire wrote. "All fuels are at or approaching critical levels for dryness. Personnel are engaging in structure defense and strengthening control lines."