The death toll in 12 nations from the tsunami disaster has leapt to more than 114,000.
Tens of thousands of residents fled coasts in India, Sri Lanka and Thailand after unfounded warnings of possible new tsunamis Thursday.
Survivors from the Indian islands told harrowing tales. Many had not eaten for two days and people had to contend with crocodiles that were washed ashore.
Some islanders from Car Nicobar had walked for days from their destroyed villages to reach a devastated but functioning airfield, where they were shuttled out 80 to 90 at a time.
Only about 359 bodies have been found on the remote islands so far.
As the world scrambled to the rescue, survivors fought over packs of noodles in quake-stricken Indonesian streets while relief supplies piled up at the airport for lack of cars, gas or passable roads to move them.
In Sri Lanka, reports of waterborne disease such as diarrhea caused fears of an epidemic.
Paramedics in southern India began vaccinating thousands of survivors against cholera, typhoid, hepatitis A and dysentery, and authorities sprayed bleaching powder on beaches where bodies have been recovered.
The number of deaths in Indonesia stood at more than 80,000. Authorities there said that did not include a full count from Sumatra's west coast, which had not yet been fully surveyed and where more than 10,000 deaths were suspected.
Sri Lanka reported 22,800 dead, India more than 7,300 and Thailand 1,800 — though that country's prime minister said he feared the toll would go up 5,000 more. A total of more than 300 were killed in Malaysia, Myanmar, Bangladesh, the Maldives, Somalia, Tanzania and Kenya.
The disaster struck a band of the tropics from Indonesia to India to Somalia that not only is heavily populated but attracts tourists from all corners. Throughout the world, people sought word of missing relatives, from small-town Sri Lankan fishermen to Europeans on sand-and-sun holidays.
In Sumatra, the view from the air was of whole villages ripped apart, covered in mud and seawater. In one of the few signs of life, a handful of desperate people scavenged a beach for food.
As the world scrambled to the rescue, relief organizations warned that diseases could add to the death toll.
Without clean water, respiratory and waterborne diseases could break out within days, putting millions at "grave risk," the U.N. children's agency said.
"Standing water can be just as deadly as moving water," said UNICEF Executive Director Carol Bellamy. "The floods have contaminated the water systems, leaving people with little choice but to use unclean surface water."
Near Banda Aceh on Sumatra, bulldozers have dug mass graves for the bodies — in part over fears that the rotting corpses would spread disease.
At least two international organizations have tried to spread the word that corpses do not contaminate water or soil because bacteria and viruses cannot survive in dead bodies.
Donations for recovery efforts came in from all parts of the globe and the world's richest nations pledged more than $250 million in emergency aid.