BUKIT LAWANG -- Rescuers were desperately searching on Tuesday for survivors after flash floods swept through the resort town of Bohorok on Indonesia's North Sumatra island, killing a confirmed 85 people, including a Singaporean.

With 123 people missing, the death toll was expected to rise, although officials said the missing included about 50 people who were out of town when the wall of water hit.

More bodies were found on Tuesday morning in the wreckage, and mourners at a local mosque washed bodies and said prayers for the dead.

Days of heavy rain triggered a surge on Sunday night in the Bahorok River, which winds through the village of Bukit Lawang. Dozens of inns and restaurants that line its banks were destroyed by the torrent of water, mud and logs.

On Tuesday, the Bahorok River continued to rage and electricity, phones and other basic services were still out.

Hopes of finding people alive beneath the debris were fading.

'Looking at the conditions at the moment, there is a very small possibility of finding anyone alive,' said Lieutenant-Colonel Aman Depari.

Poor coordination among rescuers meant that casualty figures, including those missing, remain confusing.

Five foreigners were listed among the dead on Tuesday: Two Germans, a Singaporean aged about 66 and two Austrians. Family members of the Singaporean are understood to be making their way to arrange for his body to be brought home.

Police Sergeant Bomer Pasaribu said at least 80 people died and 123 people were reported missing. That figure did not include the three bodies discovered on Tuesday.

The once picturesque town of 2,500 has long drawn backpackers from across the world to its orangutan reserve located a kilometre up the valley from the river. Despite the devastation, officials said that the several dozen orangutans in the reserve appeared unaffected by the disaster. -- AP, AFP