As authorities launch one of the largest search-and-rescue efforts in recent Texas history, they have come under intensifying scrutiny over preparations and why residents and youth summer camps that are dotted along the river were not alerted sooner or told to evacuate.

The deadly floods that struck Texas on the 4th of July caught local officials off guard as the torrential rains caused the Guadalupe River to overflow in minutes.

Rescuers were searching for more than two dozen girls missing from a summer camp in Texas after a flash flood killed at least 50 people, 15 of them children. The Guadalupe River that runs through the Hill Country in central south Texas rose by 26ft (8 metres) in 45 minutes in the early hours of Friday,