According to the May 28, 2017 advisory of the Sri Lankan Disaster Management Center, 126 people were killed and nearly a hundred people went missing because of the floods and mudslides.
The death toll has risen to 151, while 111 people are still reported missing and 95 injured, the state-run Disaster Management Center said. "The water levels are receding, but very slowly".
Torrential rains wreaked havoc in Sri Lanka in previous days. A landslide took place inside the village and several houses are buried.
The country's southwest is often referred to as the "wet belt", IFRC said, because ample rainfall is common in the region.
The flooding was caused by the bursting of river banks. People waded knee-deep in floodwaters to reach army trucks bringing relief supplies and taking away evacuees.
Military boats and helicopters have been sent to help rescue operations.
He said that his house is now submerged under eight feet of water.
Government spokesman Rajitha Senaratne said relief operations had intensified following a break in the monsoon rains, with medical teams reinforcing hospitals in affected districts. Supported by the International Federation of Red Cross and Red Crescent Societies (IFRC) the SLRCS has been quick to respond to the situation, deploying emergency response teams at national and local levels. The World Food Program and UNDP are helping with information management.
Save the Children warned of a potential increase in dengue cases in the country. Flood waters provide the flawless breeding ground for mosquitoes carrying the disease.
"With the scale of this disaster, there are many needs - it's not just a case of attending to one thing", says Kolitha Pathirana, the Branch Executive Officer of the Galle Branch of the SLRCS.
An army officer sits on top of a moving armoured personnel carrier on a flooded road during a rescue mission in Bulathsinhala village, in Kalutara.
At least 146 people have been killed and almost 500,000 displaced in the flooding and mudslides triggered by heavy rains on Friday.
Branch volunteers continue to assess the situation and are sharing information with national headquarters on needs and damages, and on relief activities realized so far.
Another massive landslide a year ago killed more than 100 people in central Sri Lanka.
A Buddhist monk walks through a landslide site in Kalutara.
"He also expressed condolences at the loss of lives and property and said that India stands with her Sri Lankan brothers and sisters in their hour of need".
The US has said it will provide relief goods worth 150 million Sri Lankan rupees.