Spanish officials say they have found the bodies of seven people and one survivor in a boat adrift off the coast of West Africa.

Officials say a Spanish fishing boat discovered the vessel late Wednesday north of the Cape Verde Islands.

The captain of the boat said there was a foul stench on board, and that the passengers must have died a week ago.

The lone survivor, who was said to be "very weak," says at least 50 people were on the boat when it began its journey, indicating the death toll may be much higher.

Spanish authorities frequently intercept Africans trying to migrate to Europe through Spain's Canary Islands.

The migrants often travel in small, rickety boats ill-equipped for the journey, which usually begins in West African countries such as Senegal or Mauritania hundreds of kilometers away.

Last year more than 30,000 African migrants landed in the Canaries. The influx sparked a political backlash in Spain, prompting the government to step up patrols along the African coast.

This year, a little more than 8,000 Africans have made it to the Canaries.

Some information for this report was provided by AFP, AP and Reuters.