Last night, the death toll across 12 countries was rising by the hour.
The apocalyptic destruction caused by the ocean surge dwarfed the efforts of governments and relief agencies as they recovered countless corpses while trying to treat survivors and take care of millions of homeless, increasingly threatened by disease amid the rotting corpses. Thousands more were injured.
The UN launched what it called an unprecedented relief effort to assist nations hit by the tsunami triggered by a magnitude 9.0 undersea earthquake off the Indonesian island of Sumatra.
In a further threat to the region, disease could kill as many people as those killed by the wall of water, a top World Health Organisation (WHO) official warned.
While grieving families in wrecked coastal towns and resorts buried their loved ones, others, including many foreign tourists, looked for friends and relatives still missing.
"Why did you do this to us, God?" wailed an old woman in a devastated fishing village in India's Tamil Nadu state. "What did we do to upset you?"
In Thailand, where thousands of tourists were enjoying a Christmas break to escape the northern winter, many of the country's paradise resorts were turned into graveyards.
In a French-run hotel at Khao Lak on the Thai mainland, up to half the 415 guests were believed killed.
"The enormity of the disaster is unbelievable," said Bekele Geleta, head of the International Federation of Red Cross and Red Crescent Societies (IFRC) in Southeast Asia.
In Sri Lanka, hundreds died when the wave crashed into a train, wrecking eight carriages and uprooting the track it was travelling on.
So far, Indonesia has suffered the biggest number of victims, with its Health Ministry reporting 27,174 dead while Sri Lanka reported around 19,000.
India's toll of 11,500 included at least 7,000 on one archipelago, the Andamans and Nicobar. On one island, two-thirds of the population died.
Hundreds of others died in the Maldives, Burma and Malaysia. The arc of water struck as far as Somalia and Kenya in east Africa.
The United Nations said the cost of the damage will reach billions of euros.
The tremor, the biggest in 40 years, tore a chasm in the sea bed which launched the tsunami, or giant wave, which appeared to be the deadliest in more than 200 years. A tsunami at Krakatoa in 1883 killed 36,000 and one in the south China Sea in 1782 40,000.
In northern Indonesia's remote Aceh region, which was closest to the epicentre, bodies littered the streets. About 1,000 people lay on a sports field where they were killed when the three-storey high wall of water struck.
At the Thai holiday resort of Phuket, foreign tourists pored over names on hospital lists and peered at 80 hospital photos of swollen, unidentified bodies.
"My father was not there," said German yacht skipper Jerzy Chojnowski, who was looking for his 83-year-old father, who has been missing since the tsunami struck.
Many of the bodies were already decomposing in the heat, underlining the growing health risk.
Gerhard Berz, a top risk researcher at Munich Re, the world's largest reinsurer, estimated the economic cost of the devastation at over €10 billion.
More than 20 countries have pledged emergency aid worth over €45m.
In Geneva, the WHO's Dr David Nabarro said it was vital to rush medicine and fresh water to the worst-hit countries.
"We could have as many dying from communicable diseases as from the tsunami," he said.
He added there was a risk of an explosion of malaria and dengue fever, which are already endemic in southeast Asia.
Around the ring of devastation, Sweden reported 1,500 citizens missing, the Czech Republic almost 400, Finland 200 and Italy and Germany 100.