Emergency workers in Sri Lanka on Tuesday found the bodies of a woman and two children killed in a landslide, taking the toll from two days of heavy rain to 11, with thousands more forced to flee their homes.

Another five people are missing across the island, parts of which have been underwater since Sunday, a spokesman for the Disaster Management Centre said.

"Over 200,000 individuals have been displaced by the floods and are being looked after at several welfare centres," Pradeep Kodippili said.

The northern district of Kilinochchi received the highest rainfall of 373 millimetres (14.68 inches) in the 24 hours ending Tuesday morning -- more than a quarter of the annual average rainfall in the region.

The government has deployed troops to evacuate people living on slopes or in flood-hit areas and the navy and the air force have also been called in to help with relief operations.

The meteorological department says the heavy rains could continue until Wednesday.