Manila - Philippine President Rodrigo Duterte on Sunday invited Muslim rebels to join the Philippine military in the fight against ISIS militants. In a speech before the troops in Mactan in Cebu City in the central Philippines, Duterte said that he has accepted the offer of Moro National Liberation Front (MNLF) founding chairman Nur Misuari to integrate some 2,000 to 3,000 MNLF fighters into the Armed Force of the Philippines to help crush the Maute group.