Rhianne Robson of the Australian Maritime Safety Authority said Monday that a merchant ship reached the site near the Cocos Islands some 1,600 miles (2,000 kilometers) northwest of Australia and was plucking people from the water.

Robson told the Australian Broadcasting Corp. the authority received distress signals on Sunday from a boat believed to be carrying about 40 people in the remote area, and the nearest ships were asked to respond.

The boat had sunk by the time the ship LNG Pioneer reached the area on Sunday night. It plucked about 15 people from the water, and a search was under way for more.