Indonesia tsunami: Rescuers battle to reach survivors
Some of the villages in the tsunami's path simply do not exist anymore
Indonesian rescue teams are battling to reach an estimated 400 people believed to be missing since a tsunami struck small islands off the coast of Sumatra.
How earthquakes happen
Officials say a 3m-high wave crashed into the Mentawai islands after a quake on Monday, killing at least 154 people.
Rescuers are now in the region, facing bad weather and post-quake aftershocks in villages levelled by the wave.
Indonesia's president is cutting short a trip to Vietnam to visit the islands and oversee the relief operation.
Officials said Susilo Bambang Yudhoyono would fly back from a meeting with regional leaders to help deal with the tsunami aftermath.
He will also be briefed on the rescue effort on Java, where an erupting volcano has caused chaos.
US President Barack Obama, who spent some of his childhood in Indonesia, has spoken of his sadness at the deaths and offered US help if required.
Mon 25 Oct - 0600 (2300 GMT 24 Oct): Highest alert issued for Mount Merapi eruption. Villagers advised to evacuate
2142 (1442 GMT): 7.5 magnitude quake near Mentawi Islands. Tsunami watch issued.
2357 (1657 GMT) Tsunami watch lifted
Tues 26 Oct - 1300 (0600 GMT): First reports of people missing after tsunami
1402 (0702 GMT): Mount Merapi erupts
"At the same time, I am heartened and encouraged by the remarkable resiliency of the Indonesian people and the commitment of their government to rapidly assist the victims," he said in a statement.
Higher ground
At least 10 villages are thought to have been flattened by the tsunami, which was caused by a 7.7-magnitude earthquake late on Monday.
Waves reached 3m (10ft) high and the water swept inland as far as 600m on South Pagai.
The first images emerging from the Mentawai Islands show bodies being collected from empty clearings where homes and buildings once stood, now levelled by the power of the wave.
Corpses were strewn along beaches and roads, district chief Edison Salelo Baja told the Associated Press.
