Cyclone-driven downpours have triggered floods and landslides across three provinces on Sumatra, including Aceh, killing 908 people and leaving 410 still unaccounted for, according to government figures released on Saturday.
The same storm systems have also claimed about 200 lives in southern Thailand and Malaysia.
In Aceh Tamiang, on Sumatra’s north-eastern coast, survivors described picking their way through mud, scattered logs and overturned cars to an aid distribution centre set up by volunteers.
Witnesses said volunteers were handing out dry clothes and had brought in a tanker truck so people could refill plastic bottles with clean water.
Among those seeking help was 14-year-old Dimas Firmansyah, a student at a nearby Islamic boarding school.
He said the floods had cut off access in and out of the area, leaving students stranded for around a week.
He recounted how pupils took turns searching for food and resorted to boiling floodwater to drink.
Dimas appealed for national leaders to come and see the destruction first-hand, saying the community felt abandoned in the aftermath of the disaster.
Local authorities on Sumatra have urged the central government in Jakarta to declare a national emergency, arguing that such a move would unlock additional funding and resources for search, rescue and relief operations.
However, earlier in the week President Prabowo Subianto said conditions were improving and existing arrangements remained adequate, signalling no immediate shift to a higher alert status.
Environmental groups say the scale of destruction has been worsened by years of deforestation linked to mining and logging in the affected areas.
They argue that forest clearing has destabilised slopes and reduced the landscape’s ability to absorb intense rainfall, increasing the risk of flash floods and landslides.
Indonesia’s environment ministry has opened investigations into several companies suspected of clearing forests around some of the hardest-hit locations.
Officials say the operations of those firms have been suspended temporarily while the probes are carried out and that the companies will be required to undergo environmental audits.
Among the firms named by the ministry are North Sumatra Hydro Energy, which operates a China-funded 510-megawatt hydropower plant in the Batang Toru region of North Sumatra, and Agincourt Resources, the operator of the Martabe gold mine in the same area.
Aerial surveys over Batang Toru have revealed extensive land clearing that, according to the ministry, may have intensified the recent flooding.
North Sumatra Hydro Energy did not respond to a request for comment sent via LinkedIn, while Agincourt Resources did not immediately reply to an emailed query.
Reuters