The boat was found by a Mauritanian patrol boat, a Spanish Civil Guard official said. It was one of the highest death tolls this year among Africans trying to escape poverty and reach Europe's southern gateway.
The boat set out from Senegal with 150 people aboard, and after it lost power and food and other supplies ran out, travelers started dying and were thrown overboard, the official said, quoting Mauritanian authorities.
When the vessel was found Tuesday, there were 100 people aboard and two dead bodies, the official said under department rules barring her name from being published.
The boat was found in waters north of the Mauritanian city of Nuadibu.