How did the spaniards discover the philippines?

The Katipunan's existence was revealed to the Spanish authorities after a member named Teodoro Patiño confessed the Katipunan's activities to his sister, and finally to the mother portress of Mandaluyong Orphanage. Seven days after the Spanish authorities learned of the existence of the secret society, on August 26, 1896, founder "Supremo" Andres Bonifacio and his men tore their cedúlas during the infamous Cry of Balintawak that started the Philippine Revolution.