The BBC News Website has received thousands of emails from readers telling of their stories of the tsunami. Click on the map below to read their eyewitness accounts from across the region.
My partner and I were staying in Beruwela on the south-west coast of Sri Lanka when the tsunami hit. We watched from the first floor of our hotel as a wall of water swept in and tore the ground floor apart underneath us.
Waiting to be evacuated to Colombo was very frightening as everyone was fearful of another and possibly bigger wave coming. At one stage we heard (wrongly) that another wave was coming and there was panic.
Miraculously a fleet of small vehicles driven by local people arrived outside the hotel and we jumped into a minibus.
We were taken up a hill to a place of safety where we were welcomed by a family and told we could stay as long as we needed to. Amid all this death and destruction these people were trying to help us. We were shown the local mosque where hundreds of locals were cooking, collecting and distributing food and supplies for those less fortunate.
In the three days we were waiting to leave we saw many examples of ordinary Sri Lankans, many of whom had lost friends, family and livelihoods while trying to help others who were worse off. It was a very moving experience.
Alison Clarke, Chelmsford UK
My husband, my child and myself were driving along the coast in our car. Then we saw lot of people gathered at the beach and some were running along the coastal line too. We asked what happened, they told us the sea came on to the road. At the time we just thought it may be a common thing, but then suddenly two men came running in front of the vehicle and told us to turn.
People had very confused emotions and nobody knew what to do next. We saw the wave strike just 100 metres away from us. We were lucky to escape, but before long, mothers came crying ... they had lost their small children in front of their very eyes and seen them floating to the sea. They were unable to hold them since they hadn't been able to grab them under the water.
Ruwanthi Senarathne, Colombo, Sri Lanka
We were in Beruwela - Hotel Confifi. Although we planned to leave at 8AM we were delayed by an hour or so, searching for the car keys. It was a beautiful day with the sun shining brilliantly. Suddenly we came upon the people of the area who looked all flustered and were running hither and thither carrying bags and babies. A motorist shouted to us that the roads were closed and that "the sea had come in."
So we decided to turn back.
Everyone was running frantically and urged us to beat it as the sea was coming further inwards. My brother-in-law and his parents had got engulfed by the "killer" wave - the second one. They had hardly entered the hotel nearby when they were submerged by this huge wave which came dashing over them and into the hotel. Furniture was floating in the water and my aunt was hanging on to a floating table for dear life, glad when it struck a pillar and remained stationery.
My brother-in-law next went to rescue his dad, who was inside the car which was also floating in the lobby of the hotel. When he opened the car door to get his dad out, water just gushed into the car. The old man next fell in the water and a second time too, near the step of the hotel. Eight men had helped to carry the car out of the water
Jayarine Saldin-Iyne, Colombo, Sri Lanka
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Eleven of us were travelling by speedboat to Phi Phi in Thailand. One minute we were sunbathing and snorkelling and the next we were literally running for our lives up the shore in the midst of yells of, "big wave, big wave" and shouts of, "go, go" from the Thai guides and drivers.
First a seething mass of broiling water crowned by a white crest came round the shore from one direction.
Seconds later another white wall rounded the other side of the island, the waves surging towards each other.
This was the first wave and it sent speedboats flying across the tops of the waves like matchsticks. The wave left as suddenly as it came.
Ten minutes later the Thais who had been surveying the damage to their boats, now well inland, started racing along the shore gesturing frantically and yelling, "Again. Big wave. Coming again!"
Temmy Maclean, Thailand
I have been helping with the relief effort in a very modest way translating mainly for Spanish tourists with little or no spoken English.
Many of them were very bewildered often asking me if they could return to their hotels. I had to gently let them know that in most cases their hotels did not exist any more.
The Governor of Phuket sent out pleas for donations of food and clothes, which the local population immediately responded to, by our standards these people are very poor under normal circumstances, yet within 24 hrs a mountain of local aid had been collected.
That is what I call humanitarian aid.
Eduardo Loigorri, Phuket, Thailand
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We are badly affected. Numbers of low-lying islands are almost submerged. The local people are seeking refuge in small dhonis. Most of the islands are out of electricity, food and water and the sewage system is totally destroyed. The government is totally unable to send help to these small islands. Many islanders have to spend the night outside since so many houses have been destroyed.
Ayya, Male, Maldives
I was working at a resort in the Maldives. At 1100 the sea started to rise and suddenly guests and staff were fighting for our lives: the waves got so high some were nearly washed out to sea. All of our rooms were destroyed. To our horror the wave came back again, from the opposite direction, and smashed us again. All power and water are gone and all staff have been evacuated. But some resorts within sight are not affected.
Patrick, South Ari atoll, Maldives
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I was off Lombok Island on a boat, which was around 3,000 km on the other side of the tsunami, yet the usually pond-like waters off the Gili islands suddenly became choppy seas and our boatman was evidently worried. This was six hours after the tsunami hit and local news confirmed that the choppy seas was a continuation of the tapering waves from the epicentre.
Erlangga Atmadja, Lombok, Indonesia
One famous reporter from the biggest news TV station here cried her heart out when reporting live from Banda Aceh, she was devastated.
The city's like a huge dumpster, dead bodies still scattered everywhere, debris blocking the streets with possibly victims of the tsunami in those piles. Help hasn't arrived yet even there in the capital of Aceh.
People who are hungry tried to break in one grocery store only to find food covered in mud and water and bodies of people who couldn't escape at the time the tsunami hit.
Tris, Jakarta, Indonesia
I received an email from a friend who is currently about 20km from Meulaboh city in Western Aceh through his satellite phone -it's the nearest port to the epicentre of the earthquake.
He said the death toll in the region has reached at least 40,000 people and 80% of the city was destroyed, including the military facilities and several patrol boats were still missing.
The city is still isolated and the only effective transportation to the location is by helicopter since all the bridges were destroyed in the quake and tsunami wave.
There is no aid from outside until now and he is now heading to Pidie, the nearest city to find some help including to get better communication with outer region.
Welxon Zhuo, Jakarta, Indonesia
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Really big waves hit the coast of Penang, many motorists were overwhelmed and waves passed over buses and cars, mud covered went up to 100m inland.
Many people have been badly injured. I witnessed a motorist with blood gushing right after the big wave hit and some people were trying to help him and carry him to one of the hospitals.
Many more sustained heavy injuries and spinal injuries as a result of being tossed from the vehicles [especially motorcycles] and smashed to the buildings. Cars were tossed around and 30ft boats were beached.
Balamurugan, Georgetown, Penang, Malaysia
My family was sleeping soundly and I felt my body was floating then I heard the sound of crushing glasses on the refrigerator, the water in the tank flew out and I knew that was an earthquake.
I also heard the loud shouting of my neighbours. All the members of my family woke up and we all ran to the ground floor as our eight-story building was shaking. My poor grandmother could not run and she was afraid. We have never had any experience of earthquake.
After a few minutes the ground stopped shaking. I feel very sorry for the people in Indonesia, Thailand, Malaysia and India. My neighbour's son is a sailor - they haven't heard any news about him and they are so worried.
Ye Tun, Yangon, Myanmar
I was shocked to see innumerable fishing boats flying on the shoulder of the waves, going back and forth into the sea, as if made of paper. Many boats were upturned, but fishermen were still holding onto them. They also were pushed into the sea. I had never imagined anything like this could happen.
P Ramanamurthy, Andra Pradesh, India
We had just boarded a ship in Port Blair, the capital of the Andamans and Nicobar Islands, when the earthquake struck. As it pulled out - I was standing on the lower deck - when I saw the jetty crumble just below me.
We had absolutely no idea what happened. I had no idea that it was an earthquake until I was told by the ship's captain. Damage on the islands has been extensive. We have no power - we are told it will be days before it will be restored. Roads have cracked up - houses have been completely flooded. The family I was staying with managed to dash out of their house in the nick of time - their daughter was almost washed out. Their home is completely flooded.
Geeta Pandey, Andaman and Nicobar Islands
My wife and my eldest daughter were in our hotel room on the first floor in Mahabalipuram when a monster wave came in the window. I could hear them screaming and two village men came running to help but the floor split into two, leaving cracks in between and my wife's leg got stuck inside. My wife was pulling my daughter's skirt to keep her alive and away from the wave. We got out safely and went to Chennai, but it was a miraculous escape.
Rahul Thiagarajan, Chennai, India
Me and my sister were near the port when we felt a sudden movement beneath our feet. We then saw people screaming and running away form the coast. There were huge tidal waves about two metres high crashing against the port. We were really scared. It was as if the sea was swallowing the land form every direction.
Mehreen, Chittagong, Bangladesh
I was at the beach during the time this tragedy occurred. I was playing on the beach with my sister when we felt along with others on the beach the ground moving beneath our feet. We then saw huge tidal wave about 1.5m heading straight towards the coast. Everyone panicked and fled as soon as possible. My uncle lives in Chittagong and he also reported these tidal waves near the coastal front when we contacted him.
Sultana Azam, Cox's Bazar, Bangladesh
Countries in the Middle East have not helped out as much, they should help us Somalis. We are still awaiting aid and NGOs like the Red Cross are not allocating enough aid.
Amin Ali, Mogadishu, Somalia
We have been bitterly damaged by the tsunami waves here, which badly destroyed our shelters in the Hafun peninsula.
Mustapha Eyl, Somalia
My family and I have relatives in Puntland. We truly hope they are all healthy and well after the tsunami disaster. We Somalis are a people who are just recovering from a civil war and do not need any more blows to our recovery. I sincerely thank all those people and countries who are aiding the affected area of Somalia and the other countries affected.
Mohammed Said Issa, Ontario, Canada
Where are the rich Muslim nations like Saudi Arabia, UAE, Kuwait? Have they donated anything?
My dear friend in Hafun has disappeared, no-one knows where he is now, he has been lost since the day of the disaster.
Hussein Yonis, Hargeisa Somaliland
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