Rescuers have recovered bodies after flash floods and landslides killed at least 26 people and left 11 missing on the Indonesian island of Sumatra.

Monsoon rains and rising rivers have submerged nine districts and cities in West Sumatra province since Thursday.

A major mudslide caused a river to breach its banks and tear through mountainside villages in Pesisir Selatan district on Friday.

Relief efforts have been hampered by power outages, damaged bridges and roads blocked by thick mud and debris, the National Disaster Management Agency said.

Agency spokesperson Abdul Muhari said rescuers recovered more bodies on Monday, mostly in the worst-hit villages in Pesisir Selatan and its neighbouring Padang Pariaman district.

Mr Muhari said landslides buried at least 14 houses. At least two villagers were injured and rescuers were still searching for 11 people reportedly missing.

He said the monsoon rains in West Sumatra province had submerged more than 37,000 houses and buildings.

At least three houses were swept away by flash floods and 666 others were damaged.

Floods also damaged 26 bridges, 45 mosques and 25 schools and destroyed 13 roads and two irrigation system units, which in turn submerged 113 hectares of rice fields and 300 square meters of plantation, the agency said.

Heavy rains cause frequent landslides and flash floods in Indonesia, an archipelago nation of more than 17,000 islands where millions of people live in mountainous areas or near flood plains.

AP