ZAMBOANGA CITY: Telecommunication firms on Sunday cut off their services in this city to ensure terrorists would not be able to detonate bombs using mobile phones during the annual Catholic procession in honor of the Virgin Mary. Zamboanga is celebrating the month-long Hermosa Festival and the grand procession is the highlight of the event which is a long tradition in this former Spanish colony. Smart Communications and Globe Telecommunication have not issued any statement about the shutdown which lasted a few hours. It was not the first time this happened in Zamboanga City which was bombed in the past by Abu Sayyaf militants using a mobile phone to trigger detonation. Late Saturday, police authorities disrupted a thermos abandoned at a public square in Zamboanga City in southern Philippines, officials said.