Probers are also trying to locate witnesses who can identify and help in the immediate arrest of the killers of Senior Inspector Marcelo Velasco of the CPD-Service Support Unit (SSU).
Velasco suffered 13 gunshot wounds in the body and died on the spot.
Investigators are interviewing Velascos relatives to determine the motive behind the killing that took place in front of Velascos house in the Zytec Compound, Barangay Pasong Tamo, Quezon City, at around 7 p.m. Wednesday.
The victim had just opened their gate when four gunmen suddenly riddled him with bullets, then fled on foot.
Desk officer PO1 Edwin dela Cruz said so far, no one among Velascos neighbors has indicated willingness to give their account of the murder for fear of reprisal from the killers.
Dela Cruz said investigators are awaiting the results of the autopsy conducted by the Philippine National Police-Crime Laboratory (PNP-CL) on Velascos corpse to determine the type of firearms used in the murder.
Meanwhile, a 39-year-old father was killed while his 13-year-old daughter was wounded after a suspected drug addict went on a shooting rampage on Good Friday in Quezon City.
The fatality was identified as Bernardo Obniala, a resident of 171 Alcantara Compound, Banlat, Barangay Tandang Sora, Quezon City. He suffered a gunshot wound in the right side near his waist and died while undergoing treatment at the Kasual Hospital.
Desk officer Dela Cruz said Obnialas daughter Bernadette was also taken to the same hospital for treatment of two gunshot wounds in the body.
Police launched a massive manhunt for the suspect identified only as a certain Michael, also a resident in the area, who managed to escape after the shooting rampage that occurred at around 3:45 p.m. on Good Friday.
Investigation showed that the suspect, who was apparently under the influence of prohibited drugs, wielding a caliber .45 pistol, challenged everybody to a fight.
Then, the suspect fired his gun indiscriminately, hitting Obniala and his daughter.
Seeing the victims bleeding, the suspect got on his motorcycle and fled. Witnesses said the vehicle used by the suspect had no license plates.