LISBON, April 7 — Four people were missing, including a 12-year-old child, after one person was rescued alive when their boat sank today off the coast of Portugal, the coastguard said.

Rescue ships and a Portuguese air force plane were deployed to the site where it went down three kilometres from the Troia, a peninsula south of Lisbon, a coastguard statement said.

Police and firefighters were also searching beaches in the area, it added.

The fifth person on the boat was rescued by a passing vessel, the coastguard said.

Portuguese media said the boat capsized after it was hit by a large wave, tossing passengers into the water.

The Troia peninsula has several sandy beaches facing the Atlantic which make it a busy destination at weekends, especially for residents of the Portuguese capital. — AFP