Chief Inspector Donald Cabigas, town police chief, said the suspect, Teng Islah, has been known to use drugs.
He said Islah did not resist arrest but refused to talk to police investigators.
Quoting neighbors, Cabigas said Islah’s family was asleep in their home in Barangay Simsiman when he attacked them using a machete.
His wife, Bainot, died instantly while the children managed to run and were rushed by neighbors to a hospital.
Cabigas said neighbors noticed Islah becoming restive and easily irritated the past days but they did not have any idea he would become so violent as to harm his family.