Indonesian rescuers are searching for 11 people missing after a boat capsized in bad weather off the Mentawai Islands in West Sumatra province.

The incident happened on Monday afternoon AEST, the search and rescue agency said in a statement. Of the 18 people on board, 10 were local government officials.

The boat had departed Sikakap, a small town in the Mentawai Islands, and was heading to another small town, Tuapejat.

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Two boats and dozens of rescuers were deployed to find the missing people on Tuesday, officials said.

Mentawai Islands is a popular spot for surfers.

Boats and ferries are a regular mode of transport in Indonesia, an archipelago of more than 17,000 islands, and accidents are relatively common due to bad weather as well as lax safety standards that often allow vessels to be overloaded.

A ferry sank earlier this month near Bali. Of the 65 people on board, 18 died, 30 survived and 17 remain missing.