Western Mindanao Police regional director Chief Supt. Dominador Domingo identified the victims as Manuel Legal, a farmer; his children, Maribel, 10, Taro, 8, Banjie, 7, and Rene Boy, 3, all of Barangay Kanuayan, Bayug town.
Domingo said the cold blooded attack threw the villagers in the area in great fear and terror.
Domingo said the incident was only learned when Manuels wife, Diana, who came home from the market discovered that all her family members bathed with their own blood from stab wounds in different parts of their bodies.
"This could be the handiwork of those who dont fear God. It is not the work of humans," Domingo said as he directed the thorough investigation and the immediate arrest of the perpetrators.
He said the investigating police recovered the steel spears used by the attackers in the massacre of the Legal family.
The villagers in the area, according to police probers, believed that the attack could be perpetrated by a cult group.
In another development, heavily armed separatist Moro Islamic Liberation Front (MILF) rebels killed five Manobo tribesmen and seized nine others Tuesday in a village of Palimbang town, Sultan Kudarat province.
The military said the MILF rebels led by Commander Nano Pangasaan swooped down on Sitio Kutungan, Barangay Batang Bagras at about 6 p.m. Tuesday and fired at the villagers.