A t least 48 people are dead in central Texas in what officials called a "mass casualty event" after devastating flash floods slammed Hill Country, with water rescues taking place along the Guadalupe River.

Meteorologists say incredible amounts of moisture in the air fueled a storm that moved slowly over central Texas, creating conditions for fatal flash floods.

At least 24 people have died and about 20 children are missing after a catastrophic flash flood in Texas. The Guadalupe River that runs through Hill Country in central south Texas rose by 26ft (8 metres) in just 45 minutes in the early hours of Friday, according to officials, bursting its banks and damaging roads and property.