One person was killed and around 15 others remain missing after flash floods swept through Grand Canyon National Park in the US state of Arizona, authorities said.

The US National Park Service (NPS) said the flooding struck the Bright Angel Canyon and Phantom Ranch areas, where torrents of water swept people, large boulders and debris into the Colorado River.

Authorities said a 46-year-old man was found dead near Crystal Rapids, while about 15 people remain missing or unaccounted for. Search and rescue operations are continuing with support from the Arizona Department of Public Safety.

Following the flooding, 62 people were evacuated by helicopter, while additional evacuations continued from affected areas of the canyon.

The flash floods destroyed most pedestrian bridges across Bright Angel Creek, severely damaged the park's only water pipeline and forced the closure of Phantom Ranch, Bright Angel Campground and sections of the North Kaibab Trail until further notice. Park officials also asked visitors and residents to conserve water after the pipeline was knocked out of service.

The National Park Service has appealed to the public for information about hikers, backpackers or campers who were in the Bright Angel Creek corridor, Phantom Ranch or along the North Kaibab Trail when the flooding occurred. Officials are continuing to assess the full extent of the damage as search efforts remain underway.(ILKHA)