Rescue teams raced Wednesday to reach communities isolated by last week's catastrophic floods and landslides in Indonesia, Sri Lanka and Thailand as over 800 people remained missing and economic damage became more clear.

Over 1,400 were killed: at least 770 in Indonesia, 465 in Sri Lanka and 185 in Thailand, with three in Malaysia.

Many villages remained buried under mud and debris, with power and telecommunications out.

Indonesia and Thailand, both middle-income economies, have been able to mobilize extensive rescue operations, deploy military assets and channel emergency funds.

Sri Lanka is responding under far more strained conditions.

Still recovering from a severe economic crisis, it faces limited resources, foreign exchange shortages and weakened public services.

Prime Minister Harini Amarasuriya met with diplomats last week to urge them to support the government’s relief and reconstruction efforts.

Countries such as India, Pakistan and the United Arab Emirates have already launched relief efforts.

Illegal logging in Indonesia may have worsened the disaster

In Indonesia, the worst-hit country, washed-out roads and collapsed bridges have left rescuers struggling to reach some of the hardest-hit areas in North Sumatra, West Sumatra and Aceh provinces, said the National Disaster Management Agency.

There was concern that deforestation may have contributed to the disaster.

Residents and emergency workers in Padang, the capital of West Sumatra, said large piles of neatly cut timber were found among the debris.

Environmental groups said the scale of damage suggested weakened hillsides and degraded forests played a major role.