New Orleans Rescuers in Race Against Time

Rescue workers in New Orleans were racing against time today to reach survivors of Hurricane Katrina, which is feared to have killed hundreds of people along the Gulf of Mexico.

Two major breaches were detected yesterday in the intricate system of levees or embankments that protect the low-lying city from the Mississippi river and Lake Pontchartrain, causing further flooding and raising concern about outbreaks of disease.

Muddy water from the lake has been flooding into the city centre, which had escaped a direct hit when Katrina hit land on Monday, causing one of the costliest disasters in modern US history.

Officials said that while New Orleans had escaped the "worst case scenario", the flooding was the "next worst scenario".

"The situation is untenable," the governor of Louisiana state, Kathleen Blanco said. "It's just heartbreaking."

An estimated 80% of the city is under water, in some places up to 6m deep. In some places the flood water was reportedly still rising by 8cm (3") an hour while in other areas it was subsiding.

The city is sometimes described as a bowl and one official said yesterday that "the bowl is filling up". Other reports spoke of a "drowning city".

Most of New Orleans' 500,000 residents were evacuated before Katrina hit, but tens of thousands remained in their homes.

Thousands rescued in New Orleans

Thousands of people have been plucked from roofs by boat or helicopter, with the water level up to the eaves on some homes. The rescue operation continued today with emergency crews pushing aside dead bodies as they searched for survivors.

The latest reports noted a growing sense of panic in the city, most of which is without electricity. Looters have been ransacking shops.

Police and troops, including some newly returned from Iraq, have been imposing what has been described as a kind of "martial law" to control the city, imposing curfews in most parishes.

One police officer was injured overnight after being shot when he surprised a looter. Reports said there were at least two other shootings and numerous car thefts.

One man was seen carrying a large pile of jeans and was asked if he was salvaging them from his own store. According to the Associated Press, he replied: "No, that's everybody's store".

In New Orleans and along the Gulf coast, the storm hit the poor and the elderly worst. Rescuers will search attics, where many people are thought to have fled to escape the rising waters. It was feared those who did not have equipment to break through their roofs may have perished inside.

The death toll in the Mississippi county of Harrison alone is at least 100 but Joe Spraggins, the civil defence director for the county, said officials were "very, very worried that this is going to go a lot higher".

Outside New Orleans the coastal resort of Biloxi and city of Gulfport were also badly hit, as was Mobile in Alabama.

Fears of disease

In New Orleans' superbowl stadium some 15,000 survivors were taking shelter in increasingly desperate conditions, with food and water scarce, and temperatures in the 90s. There were also concerns about sanitation in the stadium and the wider city.

A huge aid operation has swung into operation, but there were reports that the city would not be properly habitable again for weeks.

Thousands of US Red Cross volunteers are involved and the Federal Emergency Management Agency (Fema) requested various military deployments, including five navy vessels and eight maritime rescue ships, which were moving to the area.

Oil prices hit new high

The US energy secretary, Samuel Bodman, said today that the Bush administration would release oil from US reserves to help refiners affected by the hurricane. He spoke after oil prices surged above $70 a barrel as oil companies assessed the damage to their rigs and refineries.

The president cut his month-long holiday short by two days and returned to the White House to monitor recovery efforts,.

He will chair a meeting with representatives from 14 federal agencies involved in the recovery operation later today and is expected to travel to Louisiana city on Friday.

Katrina has been downgraded from a hurricane to a tropical depression and was passing through the Ohio river valley.

The disaster is expected to be the worst in US history with estimates putting the cost of damage at around $25bn (£14bn).

It emerged today that the hurricane has also destroyed one source of public revenue. CNN reported that all of the city's casinos, which usually add $500,000 a day to state coffers, have been destroyed.