One of the most powerful and feared natural disasters, the large and destructive water wave known as a tsunami can challenge a jet airplane for speed. Near the coast it can beat a three-story building for height.
A tsunami is a series of ocean waves that sends surges of water, sometimes reaching heights of over 100 feet (30.5 meters), onto land. These walls of water can cause widespread destruction when they crash ashore.
On Monday 25 October 2010 at 9:42pm local time, an 7.7 magnitude earthquake struck the Mentawai Islands of Indonesia sending a 2-3 metre (6-10 foot) tsunami into the southern island of Pagai Selatan.
At the time of writing more than 400 people are confirmed dead and several hundred are missing (BBC, 29.10.10). Thousands of families are displaced and relief efforts are being hampered by heavy rain and high tides.