Australia Weather News

The death toll from floods and landslides following cyclonic rains in the Indonesian island of Sumatra has risen to 303.

Large parts of Indonesia, Malaysia and Thailand have been stricken by cyclone-fuelled torrential rain for a week, with a rare tropical storm forming in the Malacca Strait.

At least 279 people are still missing even as about 80,000 people have been evacuated and hundreds are still stranded in three provinces across Sumatra island, Indonesia's westernmost area, according to Suharyanto, the head of the country's disaster mitigation agency.

The death toll in North Sumatra has risen to 166, while 90 people died in West Sumatra.

Rescuers also retrieved 47 bodies in Aceh, Suharyanto said.

About 59,660 displaced families have fled to temporary government shelters.

"The death toll is believed to be increasing, since many bodies are still missing, while many have not been reached," Suharyanto said.

Improved weather on Saturday helped rescuers recover more bodies.

But they have struggled to reach areas hit by landslides and flash floods.

Parts of Sumatra, known for its lush rainforests, volcanoes and mountain ranges, were cut off by damaged roads and downed communications lines, and relied on transport aircraft to deliver aid supplies.

Monsoon rains over the past week caused rivers to burst their banks.

The deluge tore through mountainside village, swept away people and submerged thousands of houses and buildings in the three provinces of North Sumatra, West Sumatra and Aceh.

"There are many challenges," Aceh governor Muzakir Manaf said after declaring a state of emergency until December 11.

"We have to do many things soon, but conditions do not allow us to do so."

Rescuers need heavy equipment

Authorities used cloud seeding, which involves dispersing particles into clouds to create precipitation, to redirect rainfall away from the areas where search and rescue efforts were ongoing, said Suharyanto.

In the Agam district in West Sumatra province, nearly 80 people were missing in three villages, buried under tons of mud and rocks.

There was a desperate need for heavy equipment to reach possible survivors.

Images also showed massive piles of logs washed ashore on West Sumatra's Air Tawar Beach, sparking public concern over possible illegal logging that may have contributed to the disaster.

In Aceh province, on the northern tip of Sumatra, authorities had difficulty deploying tractors and other heavy equipment.

Hundreds of police, soldiers and residents dug through the debris with bare hands, shovels and hoes as heavy rain pounded the region.

Indonesia is frequently struck by earthquakes, volcanic eruptions and tsunamis because of its location on the "Ring of Fire", an arc of volcanoes and fault lines in the Pacific Basin.

Seasonal rains frequently cause flooding and landslides in Indonesia, an archipelago of 17,000 islands where millions of people live in mountainous areas or near fertile flood plains.

Meanwhile, at least 153 people have been killed in Sri Lanka after Cyclone Ditwah caused landslides and the worst flooding in the country in a decade.

Authorities said 191 people were missing and more than half a million have been affected nationwide.

More than 78,000 people have been moved to nearly 800 relief centres, mostly set up in schools, the Disaster Management Centre said.

Thousands of police, navy personnel and army troops have been distributing food, clearing roads and moving trapped families to safety.