More than 75 people have died and dozens are still missing after flash floods and landslides hit Indonesia and neighbouring East Timor, officials said Monday.

Floods sparked by torrential rain have wreaked havoc and destruction on islands stretching from Flores in Indonesia to East Timor, sending thousands fleeing into shelters.

The deluge and subsequent landslides caused dams to overflow, submerging thousands of houses and leaving rescue workers struggling to reach trapped survivors.

"There are 55 dead, but this number is very dynamic and will definitely change, while some 42 people are still missing," Indonesia disaster management agency spokesman Raditya Djati told broadcaster MetroTV.

At least 21 people had also died in East Timor, said an official in the tiny half-island nation that lies between Indonesia and Australia.

Many of the deaths were in Timor's inundated capital Dili.

Mud covered homes, bridges and roads in Indonesia's East Flores municipality, where rescuers struggled to reach a remote and badly-hit area because of rains and strong waves.

"The mud and the extreme weather have become a serious challenge and the debris piling up has hampered the search and rescue team," Djati said.

- 'Medicine, food, blankets' -

Scared residents flocked to temporary shelters across the remote region or took refuge in what was left of their homes.

"The evacuees are spread out. There are hundreds in each sub district but many others are staying at home," said Alfons Hada Bethan, head of the East Flores disaster agency.

"They need medicine, food, blankets."

Pounding rains challenged efforts to find any survivors.

"We suspect many people are buried but it's not clear how many are missing," Bethan said.

In Lembata, an island halfway between Flores and Timor, parts of affected villages were displaced down a mountain slope and near the coastline.

In Lembata, an island halfway between Flores and Timor, parts of some villages were swept down a mountainside by torrents of mud, ending up down on the shore of the ocean.

Earlier, road access had been cut off and local officials were forced to deploy heavy equipment to reopen the roads.

Images from Lembata showed barefoot locals wading through mud and past collapsed houses to evacuate victims on makeshift stretchers and surrounded by collapsed houses.

Fatal landslides and flash floods are common across the Southeast Asian archipelago during the rainy season.

January saw flash floods hit the Indonesian town of Sumedang in West Java, killing 40 people.

And last September, at least 11 people were killed in landslides on Borneo.

The country's disaster agency has estimated that 125 million Indonesians -- nearly half of the country's population -- live in areas at risk of landslides.

The disasters are often caused by deforestation, according to environmentalists.(AF)

•PHOTO: Floods sparked by torrential rain have wreaked havoc and destruction on islands stretching from Flores in Indonesia to East Timor, sending thousands fleeing into shelters Joy Christian AFP

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