The victim, SPO1 Aljerico Llorente, was gunned down in what local officials alleged was a "mysterious shootout" inside the Rosary Heights police precinct.
Superintendent Amerodin Hamdag, city police chief, claimed that Llorente opened fire first, prompting his escort, PO1 Alim Pagadur, to shoot Llorente.
Just a week before his death, Llorente had distributed a sworn statement to media outlets and Muslim and Christian communities here a sworn statement and evidence detailing Hamdags alleged involvement in the operations of gambling syndicates and illegal transport terminals in the city.
Fr. Jose Colin Bagaforo, convenor of a multisectoral group now initiating representations with various agencies for the speedy resolution of the case, said President Arroyo should intervene and order the technical arrest of Hamdag and Pagadur.
Two witnesses, both policeman, have reportedly hinted that they need to avail themselves of the governments witness protection program due to persistent threats they have received.