A caravan of National Guard trucks, escorted by military helicopters, drove into this embattled city early Friday afternoon carrying water, food and other relief supplies for thousands of residents who have been waiting since Hurricane Katrina pummeled the area on Monday.

They arrived just shortly before lawmakers in Washington approved $10.5 billion in emergency funding for the relief effort. The House passed the bill on a voice vote. The Senate had done so Thursday night. President Bush, who sought the funds for the Federal Emergency Management Agency, said it was a down payment on the total federal effort to rebuild the Gulf Coast, and congressional leaders promised that more money would be approved when they return in force to Washington from their summer holiday.

Bush also visited the Gulf Coast Friday, meeting with officials and residents and surveying the massive damage. He acknowledged that the initial federal relief effort was "not acceptable" but vowed that efforts were being made to remedy the situation.

The relief trucks rolled into New Orleans to cheers and jeers, as military and police officials sought to bolster their ranks to counter the chaos and looting that has besieged the city. Some of the trucks, piled high with pallets and boxes, went to the city's convention center, a hotbed of discontent as people there bitterly complained about the slow pace of rescue operations. Thousands of citizens had been directed to the center early in the week for shelter but had seen few supplies until the convoy arrived.

One resident, Michael Levy, 46, told the Associated Press, "They should have been here days ago. . . . We've been sleeping on the . . . ground like rats. I say burn this whole . . . city down."

But other people stranded there, especially some of the elderly and sick, praised the troops and the effort, especially after officials set up their equipment and began feeding the masses.

Diane Sylvester, 49, was the first person through the line, AP reported, and she emerged with two bottles of water and a pork rib meal. "Something is better than nothing," she said as she mopped sweat from her brow. "I feel great to see the military here. I know I'm saved."

Other trucks went to the Superdome, which had sheltered as many as 23,000 people during the storm and afterward. Bus evacuations there continued Friday as officials sought to get them out of the city and to a variety of cities in Texas, where better services could be provided.

Because communication and transportation in New Orleans are so difficult, it was not possible to immediately determine how many trucks were in the city or if they were supplying areas other than the convention center. But television images of the dozens of trucks in the convoy showed them moving through streets filled with water as they made their way to the convention center.

Troops traveling with the trucks were armed and their rifles were pointing skyward, the AP reported.

In Baton Rouge, Lt. Gen. Steven Blum, the senior National Guard officer, said 7,000 guardsmen will be arriving in Louisiana during the next two days, joining the almost 20,000 who flew in Thursday.

"The cavalry is coming," Blum said.

He said guardsmen will be armed but stressed that "lethal force is something we will avoid at all costs. We are here to help people."

After Blum's briefing in the morning, State Rep. Karen Carter (D-New Orleans) arrived unexpectedly and made a tearful appeal for help evacuating residents of the besieged city.

"They're dying," she said. "I need some buses and gas to get them out. This is not a game."

Among the places grappling with the refugees Friday was the New Orleans airport, which has been transformed into a giant field hospital as fleets of military and Coast Guard helicopters disgorged the sick, the injured and the bedraggled from the heart of the flooded city for triage and treatment.

Some were carried out on stretchers and moved along on baggage carts. Others walked on their own, ducking to avoid chopper blades; while still others supported themselves with walkers. Some were evacuees from the Tulane University Medical Center accompanied by teams of physicians and nurses in green scrubs.

While the evacuation was continuous Friday morning, with aircraft arriving roughly every two minutes, there were still many injured and sick awaiting transportation, including about 200 patients at Charity Hospital who have been waiting for days for rescue.

Late in the afternoon, tragedy struck again for one group of evacuees. A bus taking people from the Superdome in New Orleans to northern Louisiana overturned on Interstate 49. At least one person was killed and 10 others hospitalized, according to the Web site of the Opelousas, La., Daily World newspaper.

Residents here awakened Friday to another harrowing day, starting with a spectacular looking fire accompanied by explosions in a riverfront chemical depot a few miles south of the French Quarter that sent huge plumes of smoke billowing across the city. The fire prompted rumors and speculation of a toxic cloud that turned out to be unfounded.

Walter Maestri, head of emergency management for Jefferson Parish, came on talk radio four hours after the explosions to reassure citizens that "it was not the major incident we thought it was."

A second fire of unknown origin broke out about 10 a.m. EDT in downtown New Orleans.

New Orleans was swept all night by unconfirmed reports of gunshots and random violence, spread on talk shows, TV and the Internet, with no one in authority appearing to know anything one way or the other.

The situation prompted a plea from Maestri Friday morning.

"There are a myriad of rumors out there," he said on WWL talk radio. "Everybody knows that this and that is happening. Everybody is hearing this and that. We don't know. We've got to stop dealing with rumors. We're afraid of the dark right now and everything's dark. Please, all citizens of Jefferson Parish, we're not holding anything back. What we know, we're sharing."

Jefferson Parish is just west of New Orleans on the Mississippi River.

Other officials appeared distraught and confused.

New Orleans Mayor Ray Nagin appeared on a local talk show and in a rambling interview -- that was replayed over and over through the night -- cursed and yelled and ultimately dissolved in tears.

"Get off your asses and let's do something," he said at one point.

"I'm at the point now where it don't matter," he said. "People are dying. They don't have homes. They don't have jobs. The city of New Orleans will never be the same."

Michael D. Brown, head of FEMA, made the rounds of the morning talk shows and was grilled aggressively about the situation. "By Sunday, I'll have 30,000 National Guard troops . . . We're securing the city," he said on NBC's "Today" program. "We're going to fix the problem and stop that lawlessness. . . . It's a growing and continuing disaster. . . . I think we'll start seeing major improvements over the next several days."

Later, the Congressional Black Caucus held a news conference in Washington to express frustration with the rescue effort -- and the continued lack of help for many of the mostly poor and black victims.

"I'm ashamed of America. I'm ashamed of our government," said Rep. Carolyn Kilpatrick (D-Mich.). "I'm outraged by the lack of response by our federal government."

Staff writers Jacqueline Salmon in Baton Rouge and Lexie Verdon in Washington contributed to this report. Barbash and Deane reported from Washington.