Authorities in Bangladesh intensified efforts on Wednesday to deliver food and drinking water to millions of people struggling after heavy rain unleashed catastrophic flooding across a quarter of the country.
Bangladesh is considered one of the world's most climate-vulnerable countries, with a 2015 analysis by the World Bank Institute estimating about 3.5 million Bangladeshis are at risk of river flooding every year, reports Reuters.
Prime Minister Sheikh Hasina said the government was working hard to rescue people trapped in the floods and provide relief.
"We deployed different agencies, including the army, navy and air force to rescue people. In some areas, we have ensured that people are airlifted," she said, adding that waters may recede soon but the southern part of Bangladesh was likely to be swamped, too.
On Wednesday, at least 17 of the country's 64 districts, mostly in the north and north eastern Sylhet region, were reeling from the natural disaster.
Authorities said at least 36 people had been killed and about 4.5 million people stranded so far. The floods are also threatening to disrupt agriculture, infrastructure, and clean water supply.
Mohammad Mosharraf Hossain, Sylhet division's chief administrator, said 365 medical teams were trying to reach flood-affected areas to provide tablets to purify water for drinking.
Sylhet region is among the worst affected, with several areas also without electricity.
"We are making frantic efforts to ensure there is food and drinking water for all the affected people," said Atiqul Haque, director general of Bangladesh's Department of Disaster Management.
Large swathes of farm villages were submerged. Rescue teams used boats to supply drinking water, medicine and food to people perched on higher ground and government buildings.
"Many people are in dire need of food and drinking water," said Enam Ahmed, 45, a resident in worst-hit Sunmaganj district.
"There is water everywhere but no drinking water. Flood shelters were crammed with people but they are not getting enough food," he said.
International aid organisations working in Bangladesh said the situation was extremely grim and the scale of the impact was becoming apparent as communications were being restored.
"Shelters are overwhelmed as many schools and other shelters where people would normally take refuge were inundated with water as well," said Hossain I Adib, acting country director for WaterAid, Bangladesh.
The crisis in Bangladesh has been worsened by rain water cascading down from the surrounding hills of India's Meghalaya state, including some of world's wettest areas like Mawsynram and Cherrapunji, which each received more than 970mm (38 inches) of rain on Sunday, according to government data.