At least 20 hikers are missing after a flash flood swept through the Grand Canyon.

The National Park Service was searching for those who were in the Bright Angel Canyon and Phantom Ranch area when the torrent struck Saturday.

Those being looked for include hikers who were on the North Kaibab Trail between the trailhead and Phantom Ranch, at Bright Angel Campground, or in “the Box” north of Phantom Ranch.

Dozens of people have already been evacuated.

Park officials reported that torrential monsoonal rains caused water levels to surge rapidly through Bright Angel Canyon around 2:30 p.m.

Dramatic footage shows a wall of muddy, chocolate-brown floodwater violently churning down the canyon floor, tearing through trail corridors and sweeping away debris, logs and vegetation.

National Park Service (NPS) search and rescue crews launched an immediate airlift response, safely evacuating over 50 individuals from the historic Phantom Ranch camping area, according to a social media post by the Grand Canyon National Park.

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