Police said ABC president Jerome Bautista, chairman of Barangay Ricarte Norte here, was about to enter the gate of his house when two unidentified men approached him from behind and riddled him with bullets.
Empty Armalite shells were found two meters away from the crime scene.
Bautista, who had been a barangay chairman since 1988, was also a member of the provincial board being the president of the provinces Liga ng mga Barangay. He was a known supporter of Quirino Rep. Junie Cua.
Chief Inspector Bernard Baui, Diffun police chief, told reporters that Bautistas murder might have been triggered by the victims intense campaign against wood smugglers in his barangay.
"We have witnesses who could establish the identities of the killers," Baui said. He, however, did not discount the possibility that the killing was politically motivated.
Diffun officials, led by Mayor May Calaunan, condemned Bautistas killing and called on residents of Barangay Ricarte Norte to cooperate with investigators in solving the case.
In January 1999, then ABC president Morjil Valencia, chairman of Barangay Bonifacio, was abducted in Maddela, Quirino after leaving the house of Quirino Gov. Pedro Bacani.
Seven days later, his body was found on the bank of the Cagayan River in Barangay Tallungan, Aparri, Cagayan, 300 kilometers away from where he was believed abducted.
After three months of investigation, the National Bureau of Investigation implicated Bacani and some members of the defunct Presidential Anti-Organized Crime Task Force (PAOCTF) in the abduction-slaying.
However, the Department of Justice dismissed the charges due to lack of direct evidence linking the governor and the PAOCTF members to the crime.