The death toll from catastrophic floods and landslides on Indonesia’s island of Sumatra has climbed to 303, officials confirmed on Saturday, as rescue teams continue efforts hampered by destroyed roads, severed communications, and ongoing severe weather.

Cyclone-driven storms have battered large parts of Indonesia, Malaysia, and Thailand for more than a week, with a rare tropical system forming in the Malacca Strait and unleashing torrential rains across the region.

Indonesia’s National Disaster Mitigation Agency (BNPB) chief Suharyanto said at least 279 people remain missing, while nearly 80,000 residents have been evacuated from affected areas. Hundreds more are stranded across three provinces in Sumatra, the country’s westernmost major island.

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“The northern part of Sumatra has been hardest hit,” Suharyanto told reporters. “Roads are cut off, communications infrastructure is destroyed, and landslides are blocking access for rescue operations.”

Aid deliveries ongoing

Helicopters have been deployed to deliver food and critical supplies into isolated regions, including North Tapanuli, where officials are struggling to reopen a major route linking the district to Sibolga on the western coast.

“We are trying to open the route from North Tapanuli to Sibolga, which is the most severely cut off for a third day,” Suharyanto said, adding that dozens of people remain trapped along damaged stretches of roadway and urgently need assistance.

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He also noted attempts by desperate residents to raid aid deliveries in Central Tapanuli, which is also among the hardest-hit districts. The military will reinforce relief operations on Sunday to help maintain order and expand rescue capabilities.

Across the Malacca Strait in southern Thailand, flooding has also exacted a heavy toll. Government spokesperson Siripong Angkasakulkiat said the number of deaths there has risen to 162, up from 145 reported earlier.

Authorities warn that the risk of further landslides and high water remains elevated as heavy rainfall continues across the region.

Floods hit Southeast Asia hard

Vietnam’s south-central and Central Highlands regions faced last week the aftermath of one of the country’s most destructive flood events in recent years, with authorities confirming 90 fatalities and 12 missing after nearly a month of relentless downpours, flash floods, and landslides.

Heavy rain has pounded the area since late October, driven by a persistent convergence of storm systems that repeatedly soaked the same provinces and overwhelmed already saturated soils. Some central localities recorded more than 1,500 mm of rain in a matter of days, according to meteorological briefings earlier in the week, setting off a chain reaction of deadly floods.

The Central Highlands province of Dak Lak bore the greatest share of the disaster. More than 60 of the confirmed deaths since November 16 occurred there, and several communes remained underwater as of Sunday. Entire neighborhoods were swept away as rivers swelled and mudslides tore through rural areas.

61-year-old farmer Mach Van Si described the moment he realized the water was rising too fast for him and his wife to escape. "Our neighborhood was completely destroyed. Nothing was left. Everything was covered in mud," he told AFP. "I just thought we were going to die because there was no way out," he said.

The couple climbed onto the sheet-metal roof of their home, where they spent two nights surrounded by floodwaters that obliterated surrounding houses.