All but one person missing after flash flooding devastated parts of the Grand Canyon has now been found, the National Parks Service (NPS) says.

Thirty people had previously been unaccounted for, but rangers "worked tirelessly" to reduce that number, Incident Commander Dave Black told reporters on Monday.

At least two people died after floodwaters struck on Saturday afternoon, wiping out footbridges and propelling boulders downstream.

Crews had "worked incredibly hard trying to get this situation under control", Black said during Monday's press conference.

This involved the airlift of dozens of people in Phantom Ranch, one of the park's hardest-hit areas, he added.

An initial 45 people were evacuated by air on Saturday, and a remaining group of 37 were later evacuated by Sunday afternoon, Black said.

"We've had a very busy couple of days," the official added.

Crews will be deployed on Tuesday morning to search for the final missing person in the area between Phantom Ranch and Cottonwood Manzanita.

Further heavy rain was forecast overnight from Monday into Tuesday, bringing an elevated risk of additional flash flooding to the area.

Black described the two individuals who died as adult males, adding he would not disclose any further details about their identities.

The NPS earlier said it had found the body of a 46-year-old man near Crystal Rapids along the Colorado River.

The "significant" flooding began in Bright Angel Canyon around 14:30 local time (19:30 BST) on Saturday, the NPS previously said.

Nikki Baggs, 41, who was among those to be airlifted out of the bottom of the Grand Canyon with her two friends, told the BBC: "The whole thing was terrifying.

"It was a beautiful day and then people were screaming, running."

Nearly all footbridges across Bright Angel Creek were destroyed, and the parks service closed down Phantom Ranch, Bright Angel Campground, the entire North Kaibab Trail to Phantom Ranch, Black Bridge, Silver Bridge and the Colorado River.

On Monday, the NPS said that preliminary assessments indicated about 40% of the Transcanyon Waterline, which delivers water for visitors and approximately 2,500 residents, was damaged or destroyed in the flood.

The Grand Canyon is one of the most popular national parks in the US, with about five million people visiting each year. The Bright Angel trail is its most popular hike.

The recent rains in the Grand Canyon area, and more widely in south-western parts of the US, are due to monsoonal showers.

A change in wind direction at this time of year pulls warm, moist air northward from the Gulf of California and the tropical Pacific, triggering storms over mountainous terrain.

The storms are difficult to pinpoint in forecasts and so can strike without warning. But because the ground is usually very dry, any heavy downpours lead to dangerous flash flooding and frequent lightning which increases the threat of wildfires.