As the death toll mounts after tidal waves swept across Asia Sunday following a 9.0 earthquake that struck near the Indonesian island of Sumatra, survivors struggle to comprehend what happened.

British tourist Caroline Woods was strolling through a beach-front market on the southern Thai resort island of Phuket Sunday when suddenly she saw people running and shouting.

The mother of four says she turned to walk through the market entrance, which faces the ocean, to see what the commotion was about.

"Normally, when you turned around there you'd see the horizon, so you'd see the sea and then you'd see the sky, and instead when I turned around all I could see was the sea. It was just the sea has just blocked the sky. It was obviously the point when this whole thing was coming in. And the people outside had obviously seen it and were screaming," she described.

Frantic to reach her children who were with her sister at the hotel, the London native ran toward her lodgings.

"The water just came over the road and my partner was trying to get me to stay put and all I could think about was getting back to the children," she continued.

Ms. Woods says there was chaos all around her, but eventually she managed to reach her children, who were unharmed.

"So we were wading through the water, there were petrol barrels emptying petrol and stinging my legs, ambulances floating, [we were] treading on things, not knowing what was what, cars were floating down the road, one lady had her foot chopped off," she recalled.

The earthquake that struck off the western coast of Sumatra sent tidal waves crashing all over the region - from Indonesia to Malaysia and Thailand, to India and as far away as Somalia in Africa.

Thousands of people are dead and millions displaced in the aftermath of the biggest earthquake in four decades.

Among those killed Sunday was the grandson of the King of Thailand, 21-year-old Bhumi Jensen, who was vacationing in Phuket with his mother Princess Ubolratana.

Waves as high as 10 meters swept away everything in their path, from sunbathers and fisherman to trucks and boats. Millions of homes and businesses were destroyed across the region.

Australian Graham Doven, a publisher who has lived on Phuket for 15 years, says people there are in shock.

"There was just a lot of people stunned, you know, they were just standing around staring at what I guess were their businesses and shops, just unable to comprehend at this point," he said. "Other people were getting stuck into cleaning up already, somebody managed to actually reopen last night who lost all the walls of his establishment."

The tidal waves struck with little or no warning on the sunny Sunday morning.

Ms. Woods, who vacations every year on Phuket, worries about the future of the island and its people.

"And it's a beautiful island, the people are so lovely and now we're sitting here in this swanky hotel drinking a Singha beer and they're sitting on the beach and crying because they've got nothing left," said Ms. Woods.

She cannot understand why there was no warning about the tsunami risk after the quake struck.

"Why didn't we know this was coming? If they knew that an earthquake had happened, why didn't they know that there were likely to be these tidal waves and why didn't they tell Phuket?" she questioned.

An official with Thailand's Seismological Bureau says the country does not have an international warning system. Australian Prime Minister John Howard says his government will consider helping set up a tsunami warning system for countries around the Indian Ocean, but the program first needs to be researched.