The Federal Emergency Management Agency opened its doors here Monday to the victims of Hurricane Charley, as rescue workers continued to sift through the rubble and thousands of homeless scoured the region for bare necessities such as ice, gasoline, water and food.

Surrounded by scenes of devastation and operating on little food themselves, public leaders pleaded with residents for patience. They were fearful that the heat, inconvenience and trauma of the past several days will make for a potentially dangerous post-hurricane period if people begin fighting among themselves or try to move power lines without waiting for utility crews.

Three days after the worst hurricane in 40 years struck southwest Florida, several barrier islands off the coast near Fort Myers remained closed to all but emergency vehicles. Although most of the damage on the exclusive islands was to trees and vegetation, Sanibel Island Mayor Marty Harrity said residents have been prohibited from returning to their homes because of uncertainty about the structural integrity of four bridges.

"Nothing is going to please me more than to say, 'Guess what, folks: We're going back to paradise,' " he said from an improvised city hall at the Fort Myers Holiday Inn. Harrity later said residents would be allowed to return Wednesday morning.

By the numbers, the situation on Day Four looked like this: 19 dead, 4,000 National Guardsmen activated, 25 counties declared federal disaster areas, 21 shelters with space for 2,500 people, eight Red Cross mobile kitchens, 2,000 insurance adjusters on the ground, 22,000 applications for FEMA relief filed and an estimated 120,000 Floridians out of work.

"We're thinking possibly hundreds of thousands" have been thrust into unemployment because the hurricane and tornados destroyed so many businesses, said Susan Pareigis, director of Florida's Agency for Workforce Innovation.

Local officials said there had been several arrests in recent days of people who had turned to fisticuffs in their frustration after the storm.

"As this goes on, tempers are starting to flare," said Maj. John Davenport, chief deputy of the Charlotte County Sheriff's Office. "We're going to see more domestic issues, people taking the law into their own hands."

Power was restored to two hospitals in this coastal community -- one of the hardest hit in the state -- though across Florida 800,000 customers remained in the dark and utility officials said it will likely take weeks to rebuild the electric grid in some neighborhoods. Schools in Polk and DeSoto counties are closed through Friday, Hardee and Charlotte schools until at least Aug. 27. In at least three counties, early voting for the state's Aug. 31 primaries has not begun.

Insurance industry officials estimated the damage at between $10 billion and $14 billion. FEMA announced it had allocated $10 million for travel trailers and $10 million for mobile homes to meet a request for housing for 10,000 people.

Although thousands still struggled with daily needs of food and shelter, officials began to turn their attention Monday to the longer-term challenge of rebuilding communities from scratch. At the heart of the effort is FEMA, which dispatched more than 800 people to Florida, many to the Harold Avenue Recreation Center on the edge of Port Charlotte.

"This is one-stop shopping," said FEMA spokesman Jay Eaker, as staff members began to set up tables, chairs and computers. In the coming days, representatives of several state and federal agencies would be available to "handcraft a long-term recovery package" for each person. Depending on a person's situation, hurricane victims may be eligible for assistance from the Department of Veterans Affairs, the Small Business Administration, the Agriculture Department and other agencies.

On the highways and airstrips, help poured in. The Pentagon's giant C-17 aircraft flew in ice and water, and caravans of utility crews, police cruisers and fuel trucks arrived from every direction.

Yet the devastation wrought by Charley made it difficult for even the rescue teams to operate. At the community center, FEMA crews installed telephone lines but were awaiting a satellite truck to plug them into and a generator to power the building. Staff members lent out the FEMA flashlight so people could navigate the pitch-black bathrooms.

Seated at a table in the steamy, dark gymnasium, Charles and Dorothy Romano were told they needed to apply for aid by phone -- but they have no phone service in their trailer park.

"We were told we were going to get a check right away," said Charles Romano. Although he acknowledged that FEMA was not to blame, Romano, 77, was visibly frustrated. "As you can see, FEMA didn't do nothin' for us."

Like many in the region, the Romanos have been subsisting on canned tuna, cold cereal and the occasional grilled hot dog served by the Salvation Army. The handful of restaurants operating beyond the affected area did a thriving round-the-clock business despite shortages. Some residents spent their day moving from one line to another in search of ice, gasoline, diapers, a generator or laundry service.

"We are basically lost," said Don O'Neal, 39. A mechanic who repairs county school buses, O'Neal said the house he is renting lost much of its roof and has serious water damage. "I can't get to work until I get our living arrangements worked out."

And the weather refused to cooperate. Monday opened with a 90-degree sun and concluded with a downpour, raising the prospects that already damaged roofs would collapse under the weight of the water.

About 100 of Sanibel Island's 6,000 residents ignored evacuation orders Friday, Harrity said. Financial losses on the island -- a haven for southwest Florida's wealthy elite -- could be large, but Harrity would not venture an estimate. Many islanders filtered through the Holiday Inn lobby Monday expressing frustration, worry -- and some fatalism.

"There's nothing you can do until they let us back on," said Edgar Barnes, who owns a small printing business on Sanibel. "You've just got to grin and bear it."

One day after President Bush toured the area, the White House announced it was increasing federal assistance for debris removal from 75 percent of cost to full reimbursement. The Internal Revenue Service announced it would extend the deadline for taxpayers who had been given until Monday to file. Taxpayers in Charlotte, DeSoto, Manatee and Sarasota counties now have until Oct. 15 to file, and may claim damages from the storm on this year's return or an amended version of their 2003 return.

Asked what people outside the state can do to help, Florida Community Affairs Secretary Thaddeus Cohen replied: "Send money."

Staff writer Manuel Roig-Franzia in Wauchula, Fla., and researcher Lucy Shackelford in Washington contributed to this report.

Boats litter the shoreline of Charlotte Harbor in Punta Gorda, Fla., three days after Hurricane Charley hit. Twenty-five counties were declared disaster areas.