Ten babies and a pregnant woman were among 29 illegal immigrants arrested by police after their boat arrived at the coast in southern Spain.
The 7-meter vessel arrived at Las Jaboneras beach close to the southwestern town of Tarifa, shortly after 10 p.m. (2000GMT) Monday, said a spokesman for the ministry's office in the nearby provincial capital of Cadiz.
The occupants - three men, 16 women and 10 babies - were believed to be from sub-Saharan countries and had sailed from northwest Africa, the AP reports.
The pregnant woman was taken to a hospital for medical treatment.
In another incident, 24 Moroccans were found on a boat intercepted early Tuesday off the coast of the Granada, southern Spain.
The would-be immigrants were expected to be returned to their countries of origin once they had been identified.
Each year, hundreds of Africans seeking a better life in Europe try to reach Spain weekly by crossing the Strait of Gibraltar packed into small boats.
Many are caught, but officials estimate that thousands manage to slip through each year. Many drown while making the crossing.