Superintendent Eric Paglinawan, Cabuyao police chief, identified the victims as Mauro Amarante, 83, his daughters Alicia, 49, and Corazon, and grandson Luisito, 29.
The gunmen spared Corazon’s son Ludivico, police said.
Investigators believe a family dispute over more than two hectares of land could have something to do with the killing.
Ludivico said the gunmen barged into their home at about 1 a.m. and roused them all from sleep. They then went upstairs and shot his grandfather, aunt and mother, he said.
Ludivico said they found him hiding at the back of the door, poked their guns at him but for unknown reasons, did not shoot him.
He said his brother Luisito was in another house across their grandfather’s when he was shot dead.
In another incident, three residents of San Teodoro, Mindoro Oriental were killed when suspected communist guerrillas strafed their residence yesterday.
The victims were identified as Ruben Apolinar, 54; his wife Rodriga, 54, and their adopted child, Niña, 8. — Arnell Ozaeta, Rene Alviar and Ed Amoroso