Multiple fast-spreading wildfires have forced evacuations in parts of the Grand Canyon in the US state of Arizona, with the US National Park Service ordering visitors and residents away from its northern rim.
"Due to the advancing Dragon Bravo Fire within Grand Canyon National Park, all North Rim residents are now in 'GO' status and should evacuate the North Rim immediately," the National Park Service said in a social media post.
The Dragon Bravo Fire, which was sparked by lightning and has been burning inside the Grand Canyon National Park, has grown from 150 acres (0.607 square kilometres) in size Friday evening to 5,000 acres (20 square kilometres), a US government incident report said.
Park Service staff had already cleared the North Rim, which is less popular with tourists than the South Rim, of some 500 visitors late last week.
A second, larger fire has been burning simultaneously outside the Grand Canyon National Park and grew 20 times in size over 24 hours.
The White Sage Fire has grown from 1,000 acres (4 square kilometres) to nearly 20,000 acres (80 square kilometres), according to a separate US government incident report.
Both fires are 0 per cent contained, the report said.
The White Sage Fire is approaching Jacob Lake, Arizona, a small settlement known as the gateway to the North Rim of the national park.
More than 200 firefighters and support personnel worked to halt the uncontained fire across the weekend as it burned across a high-altitude plateau between the communities of Lonesome, White Sage and Jacob Lake.
"The North Rim of the park remains closed until further notice to support firefighting operations and ensure public safety for the Dragon Bravo Fire and the nearby White Sage Fire," the Grand Canyon National Park posted on social media.
Jon Paxton, press officer for the Coconino County sheriff's office, told AFP that a hotel and some businesses had been emptied.
"Most of the folks we evacuated were campers," he said.
"This area is high desert and mostly open forest for camping."
Visitors to the South Rim have been encouraged to monitor local conditions and stay across warnings, the National Park Service said.
Both fires started by lightning
Both fires burning across the region were started by lightning during thunderstorms -- the Dragon Bravo Fire on July 4 and the larger White Sage Fire on July 9.
"Crews encountered very extreme fire behaviour due to the dry conditions (and) gusty and erratic winds inhibiting the ability for fire fighters to safely engage the fire," the Bureau of Land Management (BLM) said.
One of the greatest wonders of the natural world, the Grand Canyon is the result of the Colorado River eating away at layers of red sandstone and other rock for millions of years, leaving a gash up to 30km wide and more than 1.6km deep.
Park Service advised against hiking into the canyon, due to extreme heat and wildfire smoke.
A 67-year-old man died on Tuesday while attempting to reach the river in hot conditions.
Last year, almost 5 million people visited the world-famous site.
Another popular site, Black Canyon of the Gunnison National Park in Colorado, was also closed Friday because of a wildfire.
ABC/AFP