Arizona wildfires and extreme heat prompt evacuations near Grand Canyon

A rapidly moving wildfire north-west of the Grand Canyon National Park in Arizona has forced the closure of the park's North Rim and triggered evacuation orders for area residents.

The White Sage Fire, sparked by lightning on 9 July, has scorched roughly 1,000 acres near Jacob Lake. As of Thursday, the blaze remains out of control and actively expanding - described as "0% contained" by officials.

The combination of high temperatures, gusty winds, and dry vegetation has created dangerous conditions, fuelling the fire's swift advance, park officials said.

Officials issued an extreme heat warning on Friday, with temperature highs of up to 115F (46C), and advised against hiking into Grand Canyon.

Park officials said a 67-year-old hiker died on Tuesday in the Grand Canyon. The hiker, from Texas, was found unresponsive on the South Kaibab Trail below Cedar Ridge, and efforts to resuscitate him failed, the National Park Service said in a statement.

Emergency responders have been battling the flames from the ground and in the air using fire retardants since Wednesday.

"Due to the fire's progression toward Jacob Lake, which is now under evacuation orders, all visitors on the North Rim are required to evacuate immediately," Grand Canyon park staff said in an alert issued on Thursday.

Part of the nearby highway, State Route 89A, has been closed until further notice, with the Arizona Department of Transportation warning drivers to expect extended delays.

The wildfire threat extends beyond Arizona.

On Thursday, all staff and visitors were evacuated from Black Canyon of the Gunnison National Park in western Colorado - about 260 miles (418km) south-west of Denver - after lightning ignited fires at opposite ends of the park.

The Upper Colorado River Interagency Fire Management Unit said on Thursday it was "working diligently with partners to respond to approximately 10 wildfires caused by lightning across the dispatch area".