BAMAKO, Mali (AP) -- Islamist fighters with ties to al-Qaida have destroyed tombs classified as a UNESCO World Heritage site in Mali's historic city of Timbuktu, a resident and U.N. officials said Saturday. Irina Bokova, who heads the U.N. Educational, Scientific and Cultural Organization, cited in a statement Saturday reports the centuries-old Muslim mausoleums of Sidi Mahmoud, Sidi, Moctar and Alpha Moya have been destroyed.