CBS News National Security Correspondent David Martin reports that with 40,000 National Guard troops already called up for duty, the Army is making preparations to send in as many as 10,000 combat troops from the active duty force.
Meanwhile, President Bush will tour the hurricane-devastated Gulf Coast region on Friday and has asked his father, former President George H.W. Bush, and former President Clinton to lead a private fund-raising campaign for victims.
"This is an agonizing time for the people of the Gulf Coast," Mr. Bush said Thursday as he stood with the two former presidents in the White House and urged patience,.
Anger mounted across the ruined city, with thousands of Hurricane Katrina victims increasingly hungry, desperate and tired of waiting for buses to take them out.
"We are out here like pure animals. We don't have help," the Rev. Issac Clark, 68, said outside the New Orleans Convention Center, where corpses lay in the open and the and other evacuees complained that they were dropped off and given nothing — no food, no water, no medicine.
CBS News Correspondent Lee Cowan says the refugees want to know where the aid is — and so do reporters, "because it seems like at times there are more of us [reporters] out here on the streets than there are emergency workers and rescue workers."
About 15,000 to 20,000 people who had taken shelter at the convention center to await buses grew increasingly hostile. Police Chief Eddie Compass said he sent in 88 officers to quell the situation at the building, but they were quickly beaten back by an angry mob.
"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."
In hopes of defusing the unrest at the convention center, Mayor Ray Nagin gave the refugees permission to march across a bridge to the city's unflooded west bank for whatever relief they can find. But the bedlam at the convention center appeared to make leaving difficult.
Meanwhile, officials declared a public health emergency along thedue to unsafe drinking water, and surveyors say the town of Waveland, 35 miles from New Orleans, was completely obliterated by Hurricane Katrina.
National Guardsmen poured in to help restore order and put a stop to the looting, carjackings and gunfire that have gripped New Orleans in the days since Katrina plunged much of the city under water.
In a statement to CNN, Nagin said: "This is a desperate SOS. Right now we are out of resources at the convention center and don't anticipate enough buses. We need buses. Currently the convention center is unsanitary and unsafe and we're running our of supplies."
Homeland Security Secretary Michael Chertoff told CBS News' The Early Show the looting in New Orleans "is outrageous" and pledged "there will be public order in the streets."
Chertoff said the government is sending in 1,400 National Guardsmen a day to help stop looting and other lawlessness in New Orleans. Already, 2,800 National Guardsmen are in the city, he said.
But across the flooded-out city, the rescuers themselves came under attack from storm victims.
"Hospitals are trying to evacuate," said Coast Guard Lt. Cmdr. Cheri Ben-Iesan, spokesman at the city emergency operations center. "At every one of them, there are reports that as the helicopters come in people are shooting at them. There are people just taking potshots at police and at helicopters, telling them, `You better come get my family."'