Superintendent Dominador Ventura, who heads the task force specially created by the Department of the Interior and Local Government, backed previous claims by the Ilocos Sur police that the killing was work-related.
But Ventura brushed off any alleged links of former Gov. Luis "Chavit" Singson to the incident due to lack of material evidence.
Ilocos Sur police director Frank Cimatu earlier said they were zeroing in on guns-for-hire in Chan’s assassination.
Ventura said they have their hands full in the investigation although he refuses to give details "to avoid leading the public into something we are not sure yet."
Singson’s political opponents have insinuated his alleged involvement in the ambush-slaying because Chan testified against him during the hearings of the Senate Blue Ribbon Committee last year.
Ventura hinted that they have a gun-for-hire in their custody although he admitted that no witnesses have surfaced yet to shed light on the killing.
Earlier, Abelardo Estrada, president of the Integrated Bar of the Philippines’ Baguio-Benguet chapter, pressed the Arroyo administration to look seriously into the case.