The M7.7 earthquake took place at 14:42:22 UTC (09:42:22 Monday evening) on 25 October 2010 off the west coast of Mentawai Islands, Sumatra, Indonesia. The Mentawai earthquake and tsunami caused damage and at least 450 deaths in the Mentawai Islands off the western coast of Sumatra, Indonesia. Five minutes after the earthquake, the Indonesia Meteorological, Climatological and Geophysical Agency (BMKG) issued a national warning for a local tsunami, and the Pacific Tsunami Warning Center (PTWC) and Japan Meteorological Agency (JMA) issued local tsunami watches seven and nineteen minutes after the earthquake, respectively, to Indian Ocean countries; national authorities were then responsible for issuing warnings to their populations on the tsunami threat to their coasts.

The ITST-Mentawai Coordination Team (ICT) consisted of representatives, experts, and scientist from UNESCO Jakarta, the Intergovernmental Oceanographic Commission (UNESCO/IOC), The Indonesian Ministry for Research and Technology, Jakarta Tsunami Information Center (JTIC), and the International Tsunami Information Centre (ITIC).  

The tsunami did not cause any damage to the coast in Sumatera mainland. It mainly affected the Mentawai Islands, a chain of islands and islets approximately 150 km offshore of West Sumatera. Thus, all post-tsunami survey team were focusing their investigation in Mentawai regency, no investigation was conducted on the coast of Sumatera main island.  Five teams conducted the post-tsunami survey in Mentawai within the first month following the event. Each team comprised of both international and national expert/scientist.