Police have started an investigation after a yacht caught fire and sank 90 kilometres off the coast of Ameland late on Tuesday evening, without calling for help.

Rescue workers in boats and helicopters searched the area for survivors all night but none were found. Ships from nearby wind farms also helped in the search, which has now been called off.

The German coast guard alerted the Dutch service following a message from a ship that had seen the fire. A plane that had been patrolling the zone went to the location and found the yacht, which sank moments later.

The yacht had not activated its identification and location system, the coast guard said, which made it difficult to see where the ship had come from or whether it was experiencing problems.