The Washburn Fire in Yosemite, California, has burned at least 3,221 acres as of Tuesday (12 July), authorities said.
Some of the world's oldest and largest sequoia trees are threatened by the blaze, which broke out last Thursday (7 July).
This footage, from the Fire Integrated Real Time Intelligence System (FIRIS), shows an aerial view of the fire burning on Saturday (9 July).
More than 500 giant sequoias, most of which are over 2,000 years old, are close to the fire, but have avoided serious damage from the flames so far.
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