Teams from the Indian Navy have joined rescue efforts of Sri Lankan authorities in flood-hit regions as the death toll in the country's worst torrential rains since 2003 climbed on Tuesday to 193.
The Disaster Management Centre (DMC) said the adverse weather condition had left 112 people injured.
Nearly 600,000 people have been forced to abandon their houses, with thousands suffering structural damage from flood inundation and landslides, it said.
The weather has begun to clear, and many of the more than 100,000 people, evacuated over the weekend, had returned home to clear debris and mud from their waterlogged homes.
Read | Sri Lanka floods: Death toll rises to 146, 112 still missing; rescue operations on
More than 80,000 others remained in relief camps as their homes were either destroyed or wiped out.
The Indian contingent of more than 300 navy personnel was assisting in the relief, with divers searching the brackish waters and medical teams seeing patients in makeshift tents set up at shelters.
INS 'Shardul' has nearly 200 personnel on board, including specialised rescue, diving and medical teams, as well as a large amount of relief material and Gemini inflatable boats.
INS 'Kirch' was carrying 125 personnel. It had diving teams, relief supplies, inflatable gemini boats and a mobile medical teams.
A third Indian naval ship arrived on Tuesday, bringing relief supplies including rice, lentils, sugar, milk and blankets for the displaced.
"Secy to President of SL and SL Navy chief receiving symbolically the relief material on board the 3rd relief and rescue ship INS Jalashwa," the High Commission of India in Colombo tweeted.
Lankan army trucks transported drinking water and food to affected areas. Helicopters ferried medicine, relief supplies and inflatable boats to remote areas, while small vessels plied the floodwaters in search of people.
Lankan cabinet spokesperson Rajitha Senaratne said foreign assistance is continuing to flow in with India, China and Pakistan among the countries sending ship loads of humanitarian aid.
The rebuilding effort was well underway with the government approving Rs 2.5 million for every damaged house. Over 900 hosues in 15 districts have been completely destroyed, the spokesman said.
The disaster is described as one of the worst-ever calamities since the 2003 floods. The official death toll was at 193, with 94 others listed as missing, the Colombo Gazette reported.
The MeT department in its weather forecast said the cyclonic storm MORA is expected to get weakened when it enters Bangladesh and the possibility for heavy rain and strong winds will be reduced by Wednesday.
However, under its influence cloudy skies, windy and showery conditions are expected over the country. The MeT department warned that the sea area off the coast extending from Puttalam to Trincomalee via Kankasanthurai and sea area off the coast extending from Galle to Batticaloa via Hambantota can be very rough at times as the wind speed can increase up to 70-80 kmph.
There were scattered showers in many parts of Sri Lanka in the past 24 hours but flood waters were rapidly receding, officials said. State television broadcast called for public assistance to clean drinking wells contaminated by the monsoon floods.
Lanka's water supply minister Rauf Hakeem said 40 per cent of those affected did not have access to piped drinking water, and there was an urgent need to clean contaminated wells in flood-affected areas.
"Our workers have volunteered to join a major clean up," the minister said, adding that water distribution stations were flooded, disrupting the piped supply.
In total, 545,243 people of 142,811 families were affected by the weather calamity. The South-West monsoon unleashed torrential rains, which ravaged fourteen districts in the western and southern parts on Friday and Thursday.
The DMC had issued an urgent evacuation warning last evening instructing residents living along the Kelani river and within the Divisional Secretariats of Kollonnawa, Kaduwela, Wellampitiya, Kelaniya, Biyagama, Sedawatte, Dompe, Hanwella, Padukka and Avissawella to move to safer areas.
It said water levels in the Kelani river were rising rapidly as indicted by the water gauges at Nagalagam Street, Hanwella and Glencourse and warned residents to move away from the vulnerable area as it was under an imminent flood threat. Those living along the banks of Nilwala Ganga, The Gin Ganga and Kalu Ganga were also asked to move to safer areas because of the rising water levels.
Meanwhile, the DMC requested the people to be vigilant on rising water levels. "Showers or thundershowers will occur at times in the Western, Sabaragamuwa, Southern, Central and North-western provinces. Heavy falls (about 150 mm) can be expected at some places," it said.
Charities have warned on Monday that thousands of people affected by the floods and landslides are at the risk of potential fatal diseases such as dengue fever, as the death toll from the disaster continued to rise.
On Prime Minister Ranil Wickremesinghe's orders, Rs two billion have been set aside to help the small and medium scale businesses destroyed by the floods, Senaratne said. Senaratne has rejected criticism that the goverment was not prepared to face the disaster.
The government came under immense criticism over the absence of Minister of Disaster Management Anura Yapa who has not returned from a disaster management conference in Mexico.
Wickremesinghe left the country yesterday for medical treatment after postponing the visit over the last 18 months, Senaratne said. Sri Lanka had sought international assistance, with India sending three naval ships laden with supplies in the last a couple of days.
Following India's lead in sending out emergency relief to Sri Lanka, more countries started pledging assistance to provide relief to the flood victims. Australia has said it would provide 500,000 dollars. A Pakistani relief ship was also expected to arrive later today. At least three Chinese ships will come on Thursday.