Rescuers in Indonesia are searching for at least 400 people who have been reported missing, many believed to be buried under landslides, after cyclonic rains caused disastrous flooding nearly a week ago.
The death toll on the island of Sumatra has risen to more than 440, the government says.
Aid has been sent into affected areas by air and by sea, but some villages have yet to receive anything, and there are reports of people stealing food and water to survive.
Some foreign aid has arrived, with Malaysia sending medical supplies to Aceh, one of the worst-hit provinces.
Millions have been affected by heavy rains across South-East Asia, including Thailand, Malaysia, and the Philippines.
An exceptionally rare tropical storm, named Cyclone Senyar, caused catastrophic landslides and flooding in Indonesia, with homes swept away and thousands of buildings submerged.
People are missing in Aceh, North Sumatra, and West Sumatra, the National Disaster Management Agency said.
There are two cities that require full attention due to being isolated, namely Central Tapanuli and Sibolga, agency head Suharyanto was quoted as saying by AFP news agency.
In Sungai Nyalo village, about 100km (62 miles) from West Sumatra's capital Padang, floodwaters had mostly receded on Sunday, leaving homes, vehicles, and crops coated in thick grey mud, AFP reports.
The authorities had not yet begun clearing roads, residents said, and no outside assistance had arrived.
In another development, tech billionaire Elon Musk said he would provide free Starlink services to support communications during the emergency.
Widespread devastation affects other countries in the region; at least 170 people died in Thailand, several deaths were reported in Malaysia, and over 200 fatalities occurred in the Philippines as protests erupted against government corruption. Sri Lanka is grappling with its own crisis, with significant losses from floods and mudslides.
