In the frantic hours after a wall of water engulfed camps and homes in Texas, a police officer who was trapped himself spotted dozens of people stranded on roofs and waded out to bring them to safety,

A flash flood is a rapid rise of water along a stream or in a low-lying urban area, the National Weather Service said. Flash flooding can result from slow-moving thunderstorms, from numerous thunderstorms that develop repeatedly over the same area, or from heavy rains associated with tropical cyclones.

At least three people were killed after flash floods swept through Ruidoso, New Mexico, Mayor Lynn Crawford said in a news conference Wednesday. CBS News' Shanelle Kaul has the latest updates.