Massive flash flooding caused by record rainfall in Oklahoma and Texas has swept away hundreds of homes, forced over 2,000 people to flee and left three people dead. Up to 400 homes in the town of Wimberley, Texas, were washed away by floods along the Blanco River, which rose 26ft (8m) in just an hour, authorities said.

Describing the scene, Hays County emergency management coordinator Kharley Smith said: "We do have whole streets with maybe one or two houses left on them and the rest are just slabs. It looks pretty bad out there."

In the nearby city of San Marcos, people were ordered to evacuate their homes on Sunday morning as flood waters rose quickly around them and turned normally bone-dry streets into meandering rivers.

Several cars and trucks were submerged, and some people used inflatable lounge chairs to float down the street, in surreal scenes.

The city, which cancelled Monday's Memorial Day ceremony, said it had opened temporary shelters for residents who could not return home.

"Evacuation messages have gone out via reverse 911 and police officers and firefighters are going door-to-door to notify residents in affected areas," the authorities said in a statement.

Crews were searching for several missing people in the city and a curfew was enforced in an effort to avoid fatalities.

In Claremore, Oklahoma, firefighter Jason Farley died when he was swept away while trying to rescue 10 people in high water.

The body of a Texas man was recovered from a flooded area along the Blanco River, authorities said.

And a woman in Tulsa died in a traffic-related crash.

The extreme weather also led to thunderstorms knocking out power to more than 8,000 homes and businesses in Louisiana and Mississippi.

And a tornado briefly touched down in Houston with winds of around 100mph, damaging rooftops, toppling trees, blowing out windows and injuring several people.

The Blanco River rose above 40ft - more than triple its flood stage of 13ft and hugely exceeding its previous flood record of 33.3ft.

It swamped Interstate 35 and forced parts of the busy north-south highway to close.

Rescuers used pontoon boats and a helicopter to pull people out.

Dallas is also facing severe flooding from the Trinity River, which is expected to peak near 40ft on Monday, while the Red and Wichita rivers also rose far above their flood stages.

The National Weather Service has warned more wild weather is expected.

Strong to severe thunderstorms are forecast across a large stretch of the central and southern plains toward the Mississippi River Valley and flash flooding is expected from central Iowa into southern Texas.

This May is already the wettest on record for several cities in the southern Plains states.

Oklahoma City has recorded some 27in (69cm) of rain.

Last year the state's capital got only 4.2in.