Floodwaters were receding in some areas after a break in the rain, giving authorities a chance to deliver much-needed supplies to victims who lost everything as torrents of water swept away their homes.
Many villages were still underwater Sunday, officials said. Medical teams were dispatched to the worst-affected areas to help prevent an outbreak of waterborne diseases.
"We have the expertise to deal with this situation," Health Minister Rajitha Senaratne said, adding cholera and diarrhoea had been successfully prevented in past floods.
Heavy rains on Friday triggered the worst flooding and landslides in 14 years in the southern and western parts of the island claiming at least 126 lives.
The official Disaster Management Centre said another 112 remained missing as of Sunday morning while about 50 injured in landslides were hospitalised.
Senaratne said most of the victims were killed when mountain sides collapsed on homes.
A Sri Lankan man rows a makeshift raft on a flooded road in Wehangalla village in Kalutara district, Sri Lanka, Saturday, May 27, 2017. (AAP) Source: AAP
He said nearly 500,000 people were forced from their homes and most of them had moved into temporary shelters.
The government withdrew an evacuation order for thousands of residents in the southern district of Matara as water levels subsided.
"The threat of floods around the (river) Nilvala has subsided," irrigation department director M. Thuraisingham said.
"The flood levels near Colombo have also gone down because we did not have rain in the past 24 hours."
Water levels in Ratnapura, Sri Lanka's gem district east of Colombo, subsided but many villages in Kalutara, south of the capital, were still under water, officials said.
The military has deployed helicopters, boats as well as amphibious vehicles to rescue marooned people and deliver food and other essentials to victims.
Sri Lanka has also sought international help and India rushed a naval ship equipped with a medical team and other supplies.
Children walk in mud where a landslide occured in which 35 people are feared killed at Athwelthote in Baduraliya (AAP) Source: AAP
The United Nations said it will give water containers, water purification tablets and tarpaulin sheets while the World Health Organization will support medical teams in affected areas.
Pakistan said it was in talks with Colombo to send relief supplies. Islamabad recently gave 10,000 tonnes of rice to Sri Lanka to help drought victims.
The meteorological department said the rains ended a prolonged drought that had threatened agriculture as well as hydropower generation.
The flooding is the worst since May 2003 when 250 people were killed and 10,000 homes destroyed after a similarly powerful monsoon, officials said.
Monsoon rains last year caused flooding and landslides, killing more than 100 people.
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