At least two areas of the country’s worst-affected Sumatra island are still unreachable, as authorities struggle to deliver aid.

The death toll from devastating floods and landslides in Indonesia has risen to 442, according to a tally published by the national disaster agency, as desperate people hunt for food and water.

The National Disaster Management Agency (BNPB) on Sunday said 402 others were still missing as authorities raced to reach parts of hardest-hit Sumatra island, where thousands of people were stranded without critical supplies.

Another 402 people are missing in Indonesia’s three provinces of North Sumatra, West Sumatra and Aceh, according to the agency.

At least 600 people have died across Southeast Asia as heavy monsoon rains overwhelm swathes of Indonesia, Thailand and Malaysia. The deluges also triggered landslides, damaged roads, and downed communication lines.

The floods in Indonesia displaced thousands of people, with at least two cities on Sumatra island still unreachable on Sunday. Authorities said they deployed two warships from Jakarta to deliver aid.

“There are two cities that require full attention due to being isolated, namely Central Tapanuli and Sibolga,” BNPB head Suharyanto said in a statement.

The ships were expected in Sibolga on Monday, he said.

Desperate situation

The challenging weather conditions and the lack of heavy equipment also hampered rescue efforts.

Aid has been slow to reach the hardest-hit city of Sibolga and the Central Tapanuli district in North Sumatra.

Videos on social media show people scrambling past crumbling barricades, flooded roads and broken glass to get their hands on food, medicine and gas.

Some even waded through waist-deep floodwaters to reach damaged convenience stores.

The annual monsoon season, typically between June and September, often brings heavy rain, triggering landslides and flash floods.

A tropical storm has exacerbated conditions, and the flooding tolls in Indonesia and Thailand rank among the highest in those countries in recent years.

Climate change has affected storm patterns, including the duration and intensity of the season, leading to heavier rainfall, flash flooding and stronger wind gusts.