Flattened villages are plainly visible on the images, taken from government helicopters circling the islands.

Rescuers, who have finally reached the area, say 13 villages were washed away by the 3m (10ft) wave, and 11 more settlements have not yet been reached.

President Susilo Bambang Yudhoyono is due to visit the region later.

He cut short a trip to Vietnam to oversee the rescue effort.

A 7.7-magnitude earthquake triggered the tsunami in western Sumatra two days ago.

The first cargo plane loaded with tents, medicine, food and clothes landed on the islands on Wednesday, but rescue teams believe they have yet to reach the worst-affected areas.

Local disaster official Ade Edward said 411 people were still missing.

Bad weather has delayed the rescue effort, with boats carrying aid struggling to make the trip from Padang on Sumatra in choppy seas.