Superintendent Arnold Gunnacao, intelligence and investigation chief of the Bulacan police, said the attackers arrived on board a Mitsubishi Adventure, entered the Maritime Group outpost and identified themselves as augmentation troops from the regional Special Action Force.
They then opened fire on the policemen manning the detachment. They escaped on board two bancas waiting at the riverbank, taking with them seven M-16 Armalite rifles, a caliber .45 pistol and a caliber .38 revolver.
Killed in the attack were SPO3 Leonardo Paulino, PO1 Teodorico Collado and SPO2 Norberto Dinglasan. Wounded was PO3 Dominador Perlas.
Gunnacao said the armed mens van, with license plate WLH-161, was believed stolen from one Dr. Rosario Santos last March.
Communist rebels are being eyed in the attack. But Gunnacao said another group which had a grudge against the victims could be behind it.
The Maritime Group patrols waterways in the province, along with a Riverine Company of the Army Special Forces based in Barangay Hangga, also in Hagonoy town.
Last year, four members of the Riverine Company were slain in an ambush staged by the New Peoples Army (NPA).
Meanwhile, Pampanga policemen gunned down a member of the Rebolusyonaryong Samahang Anak Pawis, identified only as a certain Jason, in a gunbattle with at least six RSAP members in an abandoned piggery in Barangay Poblacion, Arayat town.
Police seized an M-16 rifle and an AK-47 after the clash. - With Ric Sapnu