Survivors of Hurricane Katrina rest on their cots on the floor of the Astrodome in Houston, Texas. Picture / Reuters

Survivors of Hurricane Katrina rest on their cots on the floor of the Astrodome in Houston, Texas. Picture / Reuters

Thousands of soldiers poured into New Orleans at the weekend as homeless hurricane survivors were evacuated to an uncertain future.

The dispossessed of New Orleans - most rescued at last from the city's squalid refugee centres, rooftops and highway encampments - now face uncertainty in temporary accommodation as America asks how civil anarchy can erupt so quickly.

While a massive air and bus evacuation has cleared all Hurricane Katrina survivors from inside the New Orleans Superdome and Convention Centre, where rapes, robberies and deaths were reported, those evacuated now want to know when - if - they can return to a city whose languid charms have turned to fetid horror.

In Houston, Texas, where up to 200,000 refugees have fled, 15,000 are bedded down inside the Astrodome, safe but angry and awaiting word on loved ones. Recriminations are mounting over the Government response to Hurricane Katrina.

President George W. Bush ordered an extra 7000 regular troops into the disaster zone. Authorities also dispatched 10,000 extra National Guard, bringing a total of 54,000 military personnel, 40,000 of them reservists.

But many are critical of the slow reaction to the disaster, which last Monday laid waste to an area the size of New Zealand.

Low-lying Greater New Orleans, with its population of 1.5 million, was 80 per cent flooded by Tuesday. The subsequent evacuation order made no special provision for those without transport.

Over the weekend, as soldiers from the elite 82nd Airborne Division entered the lawless city, with helicopters and Swat teams on standby, a reminder of the dangers of the past week came with a sniper who started firing near the Superdome.

As well as the hundreds of buses taking people to safety, more than 10,000 survivors were flown out of New Orleans on Saturday.

Hundreds of thousands of people have sought refuge in Texas, northern Louisiana and Florida, where local authorities say they are now struggling to cope.

As the flood waters slowly receded, bodies still lay in the streets of New Orleans.

The corpse of a black woman remained in a wheelchair outside the Superdome for the fourth day.

No toll for the tragedy was available, but a senator has said the number of dead could top 10,000 in Louisiana. Mississippi has provided a provisional death toll of 147.