Quezon City police director Senior Superintendent Magtanggol Gatdula said his men will talk with supporters and relatives of Rabaya, who was a candidate for representative of Quezon province.
"That group is the out-of-Quezon City dispatch," he said. "Other groups of the body are onto other information-gathering. Each group has its own mission. All information that each group gathers would be presented during our case conference."
Gatdula said the QCPD is pursuing three angles in the murder of Rabaya, who was found dead at the front passenger’s seat of a rented white Toyota Fortuner parked in front of a car shop along Katipunan Road, White Plains in Quezon City past midnight Saturday.
Police investigators are looking into whether Rabaya’s killing was related to politics, business or his personal life, he added.
Gatdula said they are "being careful" with this case to avoid premature releases of information that would jeopardize their efforts to resolve the murder.
"Among other leads we are exploring is the connection, if any, of casino financiers (to the murder)," he said. "We have learned that the victim used to hang out at Blue Wave on President Diosdado Macapagal Boulevard."
Over the weekend, authorities revealed that Rabaya’s last caller, who was identified as Antonia Cabiles, a coordinator of Rabaya in Quezon, may have heard details on how the crime was perpetrated.
Police investigators were able to recover a Nokia cellphone of Rabaya during ocular inspection of the crime scene.
Subsequent scanning of the cellphone unit revealed that the victim called Cabiles minutes before the incident.
Gatdula said the call was reportedly cut in the middle of their conversation, and consequently, Cabiles called Rabaya back.
"The line was left hanging that Cabiles was able to hear the details (on) how the crime was perpetrated," he said.
At this point, Rabaya merely acknowledged the call but was already unable to talk to Cabiles, he added.
In her sworn statement to police, Cabiles said that she heard a male voice say, "Wag kang kikibo kundi puputukan kita!"
Later, the same male voice threatened Rabaya, "Sige, tumakbo ka, babarilin kita," she added.
Cabiles told police she heard a vehicle arrive moments later, and that another male voice said, "Yan nga si Congressman."
After which she heard Rabaya say, "Sir, huwag po!"
At this point, Cabiles said she heard two successive gunshots.
Meanwhile, security guard Macario Ravino of Bulacan Gardens told police that he saw two men alight from a Toyota Fortuner following the gunshots.
The two men then boarded a waiting Mitsubishi Adventure, which license plate was not noted.
Past midnight Saturday, security guard Jesus Quijano reported to the police the presence of a car suspiciously parked in front of the car shop.
Policemen from the Project 4 police station went to the scene and discovered the lifeless body of Rabaya on the front passenger’s seat of the vehicle.
Rabaya had sustained two gunshot wounds – one in the nape and another in the body.
Police said the killer used a 9mm firearm.