Survivors and rescuers are battling through the devastation left by sea surges that killed more than 20,000 people on Asia's southern shores.
Mass graves are being dug even as families search desperately for missing relatives and soldiers recover bodies washed high into trees.
The extent of the damage is still not known in areas worst hit, including Sri Lanka, Indonesia, India and Thailand.
Sunday's 9.0 magnitude earthquake sent huge waves from Malaysia to Africa.
Click here for map of affected area
DISASTER TOLL
Sri Lanka: 11,000 dead
Indonesia: 4,500 dead
India: 2,958 dead
Thailand: 839 dead
Malaysia: 44 dead
Maldives: 32 dead
Burma: 30 dead
Bangladesh: 2 dead
Eyewitness accounts
In pictures: Quake disaster
At-a-glance: Countries hit
The number of dead has already soared into the thousands in Sri Lanka, Indonesia and India. Thailand was also badly hit, and the waves killed people in Malaysia, Maldives and Bangladesh.
Aid teams are heading to the huge disaster zone to offer help to national emergency services, swamped by the scale of the demands for rescue, shelter and medical attention.
Thousands are missing and many more thousands forced from their homes by the worst earthquake in 40 years that generated a wall of water speeding across the oceans.
Aftershocks were detected on Monday, sparking warnings from Indian and Sri Lankan weather officials of further, smaller surges, also known as tsunamis.
EARTHQUAKE EXPLAINED
Click below to see how the disaster unfolded
In graphics
In countries across the region, emergency workers are still assessing what happened and what can be done.
# In Sri Lanka, where at least 5,860 died and where a national disaster was announced, bodies were piled up along beaches and in hospitals. "We are struggling to cope. Bodies are still coming in," Karapitiya Teaching Hospital administrator Dr HG Jayaratne told Reuters.
# Similar scenes were reported in coastal regions of southern India and searches were still going on for those swept away from beaches or in fishing boats. "Death came from the sea," Satya Kumari, a construction worker living in Pondicherry, told Reuters. "The waves just kept chasing us. It swept away all our huts. What did we do to deserve this?"
# In Indonesia, nearest the epicentre of the undersea quake, soldiers were sent to recover bodies from trees where they were dumped by huge waves, as correspondents reported the stench of death was beginning to become overpowering. One man, Rajali, told the Associated Press news agency he could not find dry ground to bury his wife and two children.
GIANT EARTHQUAKES
1960 - Chile, 9.5 magnitude
1964 - Alaska, 9.2
1957 - Alaska, 9.1
1952 - Russia, 9.0
2004 - Indonesia, 9.0
# Every village and road on Car Nicobar, one of the Andaman and Nicobar islands, is reported to have been destroyed and officials are still trying to make contact with other communities in the Indian-owned archipelago that lies off Indonesia. "At a very conservative estimate I would say that 3,000 people are dead and as many missing," the islands' police chief SB Deol told local TV.
# Helicopters winched survivors from Phi Phi island in Thailand overnight as the navy was called in to help the rescue effort from the country's ruined holiday resorts that had been packed with tourists from dozens of countries. Many of the bodies still being recovered are said to be clad in swimsuits, with people dragged to their deaths as the tsunami smashed into beaches without warning.
# A national disaster has been announced in the low-lying Maldives islands, more than 2,500km (1,500 miles) from the quake's epicentre, after they were hit by severe flooding.
# Waves forced out from the earthquake are even reported to have reached Somalia, on the east coast of Africa.
Aid promises
International aid agencies have called for a rapid response to avert further deaths.
I have many friends on this beach and we have already found one dead. I am sure there will be many more
Tony Bridges,
Phuket, Thailand
Tell us your experiences
The European Union immediately pledged 3m euros (£2.1m) to disaster relief efforts.
The United Nations is warning that epidemics may follow the devastation, with a lack of clean water and sanitation threatening to spread disease through survivors.
Sunday's tremor - the fifth strongest since 1900 - had a particularly widespread effect because it seems to have taken place just below the surface of the ocean, analysts say.
Experts say tsunamis generated by earthquakes can travel at up to 500km/h.
IMPACT OF THE EARTHQUAKE
