The wild chaos has pushed the hurricane-hit city New Orleans into a state of anarchy on Thursday, as bodys lay forsaken, fights and fires can be seen everywhere and looters run wild in the street.
Frustration, fear and anger mounted four days after Hurricane Katrina's devastating blow inflicted potentially thousands of deaths, despite the promise of 1,400 National Guardsmen a day to stop the looting, plans for a $10 billion recovery bill in Congress and a government relief effort President Bush called the biggest in US history.
New Orleans' top emergency management official called chaos a "national disgrace" and questioned when reinforcements would actually reach the increasingly lawless city.
About 15,000 to 20,000 people who had taken shelter at New Orleans convention center grew increasingly hostile after waiting for buses for days amid the filth and the dead.
Police Chief Eddie Compass said there was such a crush around a squad of 88 officers that they retreated when they went in to check out reports of assaults.
"We have individuals who are getting raped, we have individuals who are getting beaten," Compass said. "Tourists are walking in that direction and they are getting preyed upon."
Amid scenes of utter chaos, a military helicopter came under fire as it tried to lift refugees from New Orleans' Superdome sports stadium, while a hospital was abandoned after an armed gang held up a supply lorry bringing in food, water and medical supplies.
"The truth is, a terrible tragedy like this brings out the best in most people, and brings out the worst in some people," said Haley Barbour, the governor of neighbouring Mississippi, vowing to deal with looters in his state as "ruthlessly as we can get our hands on them".
The US president, George W. Bush, who is due to visit the area today, warned there should be "zero tolerance" for those breaking the law during an emergency situation.
As many as 30,000 National Guard troops are expected to be mobilised soon, and the US Navy is sending the aircraft carrier Harry S Truman to help with rescue efforts.
Looting spirals out of control
With thousands feared dead and the city's remaining residents told to evacuate for weeks, conditions deteriorated further in submerged New Orleans as looting spiralled out of control.
Mayor Ray Nagin ordered virtually the entire police force to abandon search-and-rescue efforts and stop thieves who were becoming increasingly hostile.
"They are starting to get closer to heavily populated areas - hotels, hospitals, and we are going to stop it right now," Nagin said on Wednesday.
Tempers also were starting to flare. Police said a man in Hattiesburg, Mississippi, fatally shot his sister in the head over a bag of ice. Dozens of carjackings were reported, including a nursing home bus and a truck carrying medical supplies for a hospital. Some police officers said they had been shot at.
Earlier Wednesday, Nagin called for a total evacuation, saying that New Orleans will not be functional for two or three months and that people would not be allowed back into their homes for at least a month or two.
The first of nearly 25,000 refugees being sheltered at the city's Superdome football stadium were transported in buses to the another stadium in Houston, Texas, 560 kilometers away. Conditions in the Superdome had become horrendous: There was no air conditioning, the toilets were backed up, and the stench was so bad that medical workers wore masks as they walked around.
Asked how many people died in the hurricane, Nagin said: "Minimum, hundreds. Most likely, thousands." The death toll has already reached at least 110 in Mississippi.
If the mayor's death-toll estimate holds true, it would make Katrina the worst natural disaster in the United States since at least the 1906 San Francisco earthquake and fire, which have been blamed for anywhere from about 500 to 6,000 deaths. Katrina would also be the nation's deadliest hurricane since 1900, when a storm in Galveston, Texas, killed between 6,000 and 12,000 people.
Just outside New Orleans, gunmen held up a supply truck carrying food, water, medical supplies and pharmaceuticals, prompting officials to ask police and the US Coast Guard to help evacuate a 203-bed hospital.
"We have to close it down because we can no longer ensure the safety of our patients or our staff in that hospital," said Steven Campanini, a spokesman for Tenet Healthcare Corp.
He said there were about 350 employees and between 125 to 150 patients inside the hospital, which is not flooded and is functioning.
Looters used garbage cans and inflatable mattresses to float away with food, clothes, TV sets _ even guns. Outside one pharmacy, thieves commandeered a forklift and used it to push up the storm shutters and break through the glass.