Witness accounts from aircraft flying over a 240-kilometre stretch of shoreline say absolutely nothing remains of villages and towns in an area left underwater by Sunday's titanic earthquake and waves.

While relief was reaching other parts of Aceh, the region at the northern tip of Sumatra island, there has been no contact with the main western town of Meulaboh, other than an SOS warning that time is running out for survivors.

Vice-President Yusuf Kalla, who made an aerial reconnaisance of the western coastline and outlying islands said he saw no signs of life in Meulaboh, a town with a population of 40,000.

Kalla earlier said up to 25,000 people are estimated to have been killed when seismic shockwaves dumped towers of water on Aceh's exposed coastline. Most are likely to be from the western region's 195,000 people.

In an e-mail contact from Meulaboh, which would have been among the first places hit by the enormous waves local police said only 20 per cent of the town still stood.

Chief detective Rilo Pambudi said what remains of the town is completely cut off and still being battered by surging waters.

He said food is running out, there is looting and further catastrophe looms.

``If within three to four days relief does not arrive, there will be a starvation disaster that will cause mass deaths,'' he said in the e-mail, released by officials in Jakarta.

``The situation in Meulaboh and its surroundings is in an emergency. Meulaboh is under an SOS code.

``The economic conditions are totally paralysed, fuel is non-existent, looting is everywhere, the number of victims is rising but they cannot be evacuated,'' the e-mail went on.

Teungku Zulkarnaini, administrative head of the West Aceh district, speaking to local radio from a location outside Meulaboh where he was stranded by destroyed bridges, said he believes ``tens of thousands'' are dead in the area.

As the hours ticked by, there was still no contact with offshore islands.

A reporter with the state Antara news agency who also flew over the area said most of the coastline between Meulaboh and Banda Aceh was still underwater with few survivors among demolished buildings.

``There are no longer any signs of life along 240 kilometres. All that is left from houses and offices are only foundations,'' he said.

The air force encountered difficulties in dropping aid to victims because most of the area is under water or thick mud, relief task force leader Lieutenant Colonel Deri Pemba said.

Senior UN official Michael Enquist said Kalla's death toll estimates reflect the extent of the calamity.

AGENCE FRANCE-PRESSE