Ailing Cuban leader Fidel Castro is in "very grave" condition after three failed operations and complications from an intestinal infection, a Spanish newspaper said Tuesday.

The newspaper El Pais cited two unnamed sources from the Gregorio Maranon hospital in the Spanish capital of Madrid. The facility employs surgeon Jose Luis Garcia Sabrido, who flew to Cuba in December to treat the 80-year-old Castro.

In a report published on its Web site, El Pais said: "A grave infection in the large intestine, at least three failed operations and various complications have left the Cuban dictator, Fidel Castro, laid up with a very grave prognosis."