Sian Powell, Aceh – It was the stuff of nightmares in Aceh's capital city yesterday but it was an essential step to preventing epidemics of cholera and other diseases – an excavator working overtime scooping corpses into a truck for rapid transfer to a mass grave.

Four days after the sea swamped Indonesia's western-most province with giant tsunamis, killing thousands, corpses are still everywhere in Banda Aceh.

Lieutenant-Colonel Mailand Alexander, deputy of the Indonesian military hospital in Banda Aceh, the only major hospital still functioning in the city, said preventing disease was the first importance and said the supply of clean water was becoming critical. "We don't have any more bottles of water, so we are giving the patients the IV bags to drink," he said.

Lieutenant-Colonel Alexander said the rapid disposal of unclaimed bodies was essential, saying: "First they must be removed, then the place was to be sterilised."

The Australian Defence Force arrived in strength at Banda Aceh airport yesterday, bringing water, medicine, food and a medical assessment team. Group Captain John Oddie said the assessment team would work out how best to deploy crucial assistance to a province where thousands are dead, thousands more injured and tens of thousands homeless. A plane was also due in yesterday, bringing 50 Australian volunteers to provide humanitarian aid.

"There is so much to do," Group Captain Oddie said. "What we're trying to do is the things we do best, and work in partnership with the Indonesians."

Two Malaysian planes also arrived at Banda Aceh airport yesterday. Aid from Japan and Singapore was expected, too. After a slow start, international assistance has begun to reach those in need.

Two days ago, there were only a handful of aid posts on the stretch of highway between Aceh's two main cities situated at opposite ends of the province. Banda Aceh's general hospital remains unusable because of a sea of mud that swept through it. Crowds continue to sleep in the open. Further afield, in the worst-hit and long-isolated district of Meulaboh, a ship was scheduled to arrive yesterday with much-needed aid.

The only power in Banda Aceh yesterday was at a military hospital, which used a generator. Telephone lines remained cut, while food was in short supply.

Lieutenant-Colonel Alexander said there were not nearly enough staff to deal with the disaster. "Nurses and doctors were also affected by this emergency," he said. "Some have lost their children, some have lost houses."

Meulaboh is the district closest to the quake's epicentre and fears have grown that it may have been worst affected. General Ryamizard Ryacudu said there had been almost no communication with the district.

At the military hospital, the wounded moaned and wept. One woman roamed the dark corridors sobbing. "They're all still traumatised," Lieutenant-Colonel Alexander said. "That's understandable."