Egeland said he expected hundreds of relief flights from two dozen countries within the next 48 hours.

Indonesian Vice President Yusuf Kalla said he believed the toll in his country, the closest to the epicenter of Sunday's magnitude-9.0 quake, could be as high as 25,000. That would be 20,000 more deaths than confirmed there so far.

More than 15,000 people were confirmed dead in Sri Lanka, nearly 5,000 in Indonesia, and 4,400 in India. Hundreds of bodies are being recovered daily and thousands of people remain unaccounted for, so the toll is likely to rise significantly.

"The toll is increasing," said Brig. Daya Ratnayake, a Sri Lankan military spokesman. "We are finding more bodies."

Scores more died in Malaysia, Myanmar, Bangladesh and the Maldives. The waves raced 2,800 miles across the Indian Ocean to Africa, killing hundreds of people in Somalia and others in the Seychelles and Kenya.

Eight Americans were among the dead, and U.S. embassies in the region were trying to track down hundreds more who were unaccounted for.

Little warning

The quake off the Indonesian island of Sumatra's northern tip sent 500 mph waves surging across the Indian Ocean and Bay of Bengal in the deadliest known tsunami since the one caused by the 1883 volcanic eruption at Krakatoa — located off Sumatra's southern tip — that killed an estimated 36,000 people.

For most people around the region's shores, the only warning of the disaster came when shallow coastal waters disappeared, sucked away by the approaching tsunami, before returning as a massive wall of water.

The waves wiped out villages, lifted cars and boats, yanked children from the arms of parents and swept away beachgoers, scuba divers and fishermen.

In a scene repeated across the region yesterday, relatives wandered hallways lined with bodies, searching for loved ones at the hospital in Sri Lanka's southern town of Galle, one of the worst-affected areas. People lifted blankets and soaked clothes to look at faces in a stunned hush, broken only occasionally by wails of mourning.

A tractor brought in about 15 corpses of mostly women and children, some wrapped in white plastic sheets.

Sri Lanka hit hard

Sri Lanka, a teardrop-shaped island nation of about 20 million off the tip of southern India, was squarely in the path of the tsunami.

While the modern-looking capital of Colombo was largely unscathed, the waves caused massive damage to lower-lying coastal communities, especially on the exposed southern and eastern coasts.

In Banda Aceh, capital of Aceh province at the northern tip of Sumatra, the streets were filled with overturned cars and the corpses of adults and children. Shopping malls and office buildings lay in rubble, and thousands of homeless families huddled together in mosques and schools. The minaret of the city's 125-year-old mosque leaned precariously.

At least 3,000 people died in the city of 400,000, which was virtually unique in that Banda Aceh was destroyed by the earthquake rather than the resulting tsunami.

Tourists rush to get home

In Thailand, the government offered free flights for thousands of Western tourists desperate to leave the southern resorts ravaged by the tsunami. Chaos erupted at Phuket airport as hundreds of tourists, many bandaged and brought to the airport in ambulances, tried to get on planes.

Bodies were pulled from roadsides, orchards and beaches at Thailand's Khao Lak resort, where the Swedish tour operator Fritidsresor said 600 Swedes had not been accounted for.

Jimmy Gorman, 30, of Manchester, England, said he saw 15 bodies, including up to five children and a pregnant woman, on Phi Phi island, one of Thailand's most-popular destinations for Westerners.

Concerns about disease

The dying could continue in the stricken areas, where waves spoiled drinking-water supplies, polluted streets and homes with raw sewage, swept away medical clinics, ruined food stocks and left acres of stagnant ponds where malaria-carrying mosquitoes can breed.

"Within a few days, we fear, there is going to be outbreaks of disease," Indonesian Vice President Jusuf Kalla said. "Cholera is going to be a problem. This is going to be the most important thing in a few days."

In Geneva, Jamie McGoldrick, a senior U.N. health official, said typhoid, diarrhea and hepatitis pose dangers wherever the tsunami struck. "The biggest threat to survivors is from the spread of infection through contamination of drinking water and putrefying bodies left by the receding waters," McGoldrick said.

"Medical care is key to breaking the cycle," said Richard Aghababian, emergency-medicine chair at the University of Massachusetts Medical School and a former commander of a federal Disaster Medical Assistance Team. "If you've got a kid with cholera, isolate him so he doesn't give it to other people."

That sort of measure will be impossible in some areas, experts said. Many had a pessimistic outlook about the days ahead.

ELIZABETH DALZIEL / AP People make their way through heavy debris littering the streets of Galle, Sri Lanka, yesterday. At least 12,500 people, and possibly many more, were killed Sunday when huge waves hit the southern and eastern shores of the island nation.

But there has been an eerie silence from more impoverished areas, such as in parts of conflict-torn Indonesia, the low and slowly sinking Maldive and Nicobar islands and Myanmar, where the authorities are telling international relief agencies "next to nothing," said Simon Ingram, a UNICEF spokesman in New York.

Material from The Washington Post, Newhouse News Service and Reuters is included in this report.