Firefighters battle the Ranch Fire near Upper Lake, California, on August 2, 2018. (Photo: AFP)
Thousands of firefighters were struggling Thursday to contain two vast wildfires in California, one of which has become one of the most destructive blazes in the state's history.
The Carr Fire has scorched 126,00 acres (51,00 hectares) of land since July 23, when authorities say it was triggered by the "mechanical failure of a vehicle" that caused sparks to fly in tinderbox dry conditions.
The fire has also razed 1,465 buildings, including some 1,000 homes, making it the sixth most destructive blaze in the history of the fire-prone western state.
More than 4,200 firefighters have been deployed to battle the conflagration but they have only succeeded in containing 35 percent of it so far.
Another major blaze known as the Ferguson Fire broke out near the popular Yosemite National Park almost three weeks ago, on July 13, and was only 39 percent contained by Thursday, officials said.
It has burned 68,610 acres of land, of which 5,700 went up in smoke on Wednesday night alone.
"The high pressure system above the fire is weakening throughout the week, resulting in warmer and drier conditions. This will increase fire behavior," warned Inciweb, which provides updates on the fires.
The two fires have killed eight people, with the Carr Fire alone responsible for six of the deaths.
Other fires raging in the state include the Mendocino Complex. It's made up of two blazes, the River Fire, which is 50 percent under control after burning 35,278 acres, and the Ranch Fire, which has torched 74,890 acres and is only 33 percent contained.
Several thousand people have been evacuated as the fires swept across the state, although some have been given permission in recent days to return to their homes.