Images reveal Indonesian tsunami destruction
Aerial images from the tsunami-hit Mentawai Islands in Indonesia have revealed the extent of destruction, as officials raised the death toll to 311.
Flattened villages are plainly visible on the images, taken from helicopters circling the islands.
Rescuers have finally reached the area where 13 villages were washed away by the 3m (10ft) wave but 11 more settlements have not yet been reached.
President Susilo Bambang Yudhoyono has arrived in the region.
He cut short a trip to Vietnam to oversee the rescue effort and has been briefed by officials in the port city of Padang on Sumatra.
He then began the journey to the remote and inaccessible Mentawai Islands, where he will also meet the governor of the area.
A 7.7-magnitude undersea earthquake triggered the tsunami two days ago.
But the BBC's Karishma Vaswani, in Jakarta, says rescue teams have still not arrived at the worst-affected communities, where the scale of the damage is still unclear.
More than 300 people are still missing, authorities say, and there are growing fears that many or most of those were swept out to sea by the tsunami.
The first cargo plane loaded with tents, medicine, food and clothes landed on the islands on Wednesday.
But officials have had less luck transporting goods by boat some 175km (110 miles) across choppy seas from Padang.
"We're still looking for a means of transportation to be able to carry relief goods and personnel," local official Hidayatul Irham told the BBC's Indonesian service.
He said rescue teams dispatched to the island were unable to send back adequate reports because lines of communication with the remote islands were so bad.
Local disaster official Ade Edward said more than 400 people were still missing and 16,000 refugees had been moved to higher ground from the coastal areas.
The first images emerging from the islands, taken on mobile phones, showed bodies being collected from empty clearings where homes and buildings once stood.
Later, Vice-President Boediono and his entourage took helicopters to the island and released aerial images showing widespread destruction of buildings.
District chief Edison Salelo Baja said corpses were strewn along beaches and roads.
Locals were given no indication of the coming wave because an early-warning system put in place after the devastating 2004 tsunami had stopped working.
Ridwan Jamaluddin, of the Indonesian Agency for the Assessment and Application of Technology, told the BBC's Indonesian service that two buoys off the Mentawai islands were vandalised and out of service.
"We don't say they are broken down but they were vandalised and the equipment is very expensive. It cost us five billion rupiah each (£353,000; $560,000).
However, even a functioning warning system may have been too late for people in the Mentawai Islands.
The vast Indonesian archipelago sits on the Pacific Ring of Fire, one of the world's most active areas for earthquakes and volcanoes.
More than 1,000 people were killed by an earthquake off Sumatra in September 2009.
In December 2004, a 9.1-magnitude quake off the coast of Aceh triggered a tsunami in the Indian Ocean that killed a quarter of a million people in 13 countries including Indonesia, Sri Lanka, India and Thailand.