Multiple urban search and rescue teams from across the country that responded to the deadly floods in central Texas told CNN they were not deployed by the Federal Emergency Management Agency until at least Monday evening — days after any victim had been found alive.

The National Weather Service warned that the Guadalupe River could surge to nearly 15 feet—5 feet above flood stage—by Sunday afternoon.

The death toll has now climbed to at least 129, making it America's deadliest rainfall-driven flash flood since 1976.