Flash floods surged through in the middle of the night, but many local officials appeared unaware of the unfolding catastrophe, initially leaving people near the river on their own.

Rescue efforts included over 2,100 responders on the ground, private helicopters, drones, boats and cadaver-detecting dogs.

As crews search for missing people after flash floods killed at least 120 in Texas, cities across the U.S. grapple with rising flood waters.