A major flash flood at the Grand Canyon forced the evacuation of dozens of people and swept large boulders, metal structures and other debris into the Colorado River that runs through it, the U.S. National Park Service said. Saturday's flooding has left the park service seeking information about 15 people who may be missing or unaccounted for.

No injuries were reported but park officials warned people against accessing the closed areas.

Officials say dozens of people have been evacuated from the depths of the Grand Canyon because of heavy rain and flooding.