At least 200 others are still missing as rescue teams struggle to reach isolated communities.
According to the Disaster Management Center (DMC), more than 20,000 houses have been destroyed, forcing more than 78,000 people to move to about 800 relief centers across the country.
President Anura Kumara Dissanayake used emergency powers to speed up relief and recovery efforts after a week of torrential rains flooded homes, farms and roads and caused massive landslides.
Cyclone Ditvaha, which formed east of Sri Lanka, is expected to move towards the southern coast of India by Sunday.
Communities cut off, death toll feared to increase
Landslides have blocked roads in central Badulla district, leaving entire villages inaccessible.
The casualties included 11 elderly residents of a care home in Kurunegala, where floodwaters swept away the building on Saturday.
Social media posts also showed areas affected by landslides overnight where authorities have not yet reached, raising fears that the death toll could rise further.
A massive rescue operation is underway
Thousands of troops have been deployed, along with police, civilian responders and volunteers.
In a major operation, 69 bus passengers, including a German tourist, were rescued after being stranded for 24 hours in Anuradhapura district.
India has sent two search and rescue teams, comprising 80 personnel, and aid material, its embassy in Colombo said.
In Colombo, floodwaters from upstream districts began affecting areas around the city on Friday, including Malwana, where residents experienced the worst flooding in ten years.
As of Saturday, many homes around the city are without power, and some residents are living on the upper floors of partially flooded homes to protect their belongings.
More heavy rain expected
The government has closed schools and offices, and suspended passenger train services, as landslides, rocks and fallen trees are blocking tracks and major roads.
Meteorologists are warning of more rainfall over the weekend, increasing the risk of flooding and landslides in already saturated areas.
Edited by: Dmytro Lyubenko
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