Flash floods that swept through Texas over the Fourth of July weekend have left more than 100 people dead and dozens of others missing.

Torrential rains before dawn on Friday deluged the Guadalupe River, which burst its banks and killed dozens of people, leaving behind mangled piles of debris, trees and cars.

Even as authorities in Kerr County, Texas have repeatedly discouraged civilian volunteers from showing up to help in the search for victims of the region's historic flooding, many are, anyway.