Philippine policemen have uncovered a plan of Islamic militants to blow up Catholic churches in southern Philippines. Chief Supt. Felicisimo Khu, regional police director for Western Mindanao, said Thursday they got Intelligence report citing militants linked to Al Qaeda were planning to plant three homemade bombs in populated areas such as Catholic churches in the Philippines. Khu specifically identified three churches in the southern city of Cotabato -- the Immaculate Conception Cathedral, Rosary Heights Parish Church and Queen of Peace. In 2009, six people were killed and dozens wounded when a bomb went off outside Immaculate Conception Cathedral. \"Authorities were alerted over this threat. We ask the public to be vigilant and report to police any suspicious looking men,\" he said. Khu made the revelation after another bomb exploded in Cotabato on Wednesday morning. The bomb, fashioned from 81-milimeter mortar shell, was planted underneath a jeep parked near the gate of the Autonomous Region of Muslim Mindanao regional office. The incident is believed to be connected to the two bombings which occurred Tuesday within the vicinity of the regional hospital also in Cotabato City. Japal Guaini, mayor of Cotabato, said they put up reward money for those who could provide fresh information for the arrest of suspects in this week\'s bombing. No one claimed responsibility for the attacks but the military blamed Islamic rebel group in previous bombings.