Flash floods, mudslides and falling trees have killed at least 14 people in Sri Lanka as the island nation is battered by monsoon storms, the country's disaster centre said Sunday.

Some drowned, including three members of the same family swept away near the capital Colombo on Sunday.

Others were buried alive in mudslides, including an 11-year-old girl and a 20-year-old man, the Disaster Management Centre (DMC) said.

Nine other people were crushed and killed when trees fell on them in seven districts since the monsoon intensified on May 21, the DMC said.