Matthew Moore, Banda Aceh – More than three weeks after the tsunami that wiped out much of Aceh's west coast, aid was continuing to arrive in a chaotic manner. Lack of water, sanitation and food was causing relief experts deep concern.

This picture is revealed in the first detailed assessment of Aceh's remote west coast, a region where fishing and rice farming villagers were hit harder than those in any of Asia's tsunami-struck areas.

While the report, concluded last week and released at the weekend, highlights the huge and successful efforts by Indonesian and foreign military and aid groups to keep communities alive, it also details a long series of shortcomings that have flowed from the jumble of big and small relief groups.

In an attempt to plan a continuing west coast aid operation, 34 representatives from 14 groups – including the World Health Organisation, the Indonesian military, the Australian Government's aid arm AusAID and the International Red Cross – were taken by helicopter to four parts of the coast, where they worked for six days to produce the report. The team did not examine the capital city, Banda Aceh, and its less isolated surrounding areas, which have been better monitored and better supplied.

They found the tsunami destroyed virtually every village and town not more than 10 metres above sea level along a 170-kilometre stretch of coast. The devastation reached on average three to six kilometres inland and, along with the villages and towns, much of the road system, including 57 bridges, was wiped out.

The leader of the assessment team, Rob Holden from WHO, said a complete lack of sanitation in virtually the whole of the coast was the major risk facing an estimated 125,000 displaced people.

One of the problems was that survivors from a host of little villages were congregating in the major towns of Meulaboh and Calang, where swelling numbers posed an immediate risk of a disease outbreak. The team found prices for food and basic commodities had doubled in some areas.

The one thing in excess supply was field hospitals and highly trained foreign staff. Meulaboh had 20 surgeons at one stage. The west coast lost 50 to 70 per cent of its health services, the report said. Replacing clinics across the whole west coast was urgently needed.

Mr Holden said that while the operation "probably looks chaotic and it is chaotic", it was going fairly well given the size and location of the disaster.

Indonesia's Health Ministry reported yesterday that the tsunami death toll had risen more than 7000 to 173,981. It said 173,741 had died in Aceh and 240 in the neighbouring province of North Sumatra. Another 7249 people are classified as missing. The ministry's previous tally was 166,760.

Military sources said Indonesian troops had killed more than 200 suspected separatist rebels in Aceh province since the tsunami, including three who allegedly opened fire on soldiers repairing a damaged bridge.

The death toll signals that an informal ceasefire declared by both sides in the aftermath of the disaster never took hold, and will raise concerns about the security of the relief operation there. Army chief of staff General Ryamizard Ryacudu said the killings came in 86 separate encounters with the rebels, the state news agency Antara reported.