More than 100 people are believed to have died in a massive mudslide that hit buried scores of houses in Sri Lanka.

Disaster Management Minister Mahinda Amaraweera said the death toll in the hilly village of Haldummulla, 200km east of Colombo, was likely to surpass 100, with hundreds more missing.

"We have suspended the rescue operations because of darkness and inclement weather. There is also threat of further landslide," Amaraweera said. "We will continue from tomorrow."

The mudslide was triggered by heavy monsoon rains that have lashed the country over the past few weeks and continued as rescue efforts were underway, affecting the operations.

The military was mobilised to search for survivors trapped inside the more than 140 houses covered by mud up to their roofs. Some 500 military personnel and civilians were reportedly involved in the rescue effort.

Sri Lanka President Mahinda Rajapaksa tweeted:

Most of the victims are believed to be tea workers the local Meeriabedda plantation and their families.

Plantation worker P Arumugam said: "Everything that I saw yesterday I could not see today — buildings, the temple and shops had all disappeared. I could only see mud everywhere".