A boat capsized hurling 18 people overboard off the western coast of Indonesia.

The vessel reportedly overturned during a storm while sailing through the Mentawai Islands in West Sumatra at around 11 am on Monday.

Seven people were rescued and taken to safety, while 11, including three children, were reported missing after a large wave struck the boat, causing it to upend.

Footage shows the search and rescue crew beaming lights into the darkness as they scoured the rough seas for the missing passengers on July 14.

Rudi, head of the Mentawai search and rescue agency, said: 'Seventeen are confirmed safe. We are still confirming that the last person survived. The team is heading to the location. From what we heard from the operator, the boat was struck from the side and then flipped over.'

The passengers were said to have survived by clinging for hours onto pieces of the wrecked boat, which was headed to the town of Sikakap on the Mentawai Islands.

Boats and ferries are a common mode of transport in the archipelagic nation of Indonesia, which has more than 17,000 islands. Maritime accidents are often caused by poor weather and lax safety standards.

On July 3, a ferry sank off the holiday island of Bali, killing 18 and leaving 17 missing.