MANILA - Seven people were killed by unidentified gunmen in the northern Philippine province of Rizal early Monday, local media reported.

Police said illegal drugs may be one of the motives behind the killings in the village of San Jose, Rodriguez town.

Rodriguez town police chief Superintendent Donato Bait said the fatalities included the owner of the house who was previously jailed for drug-related offenses and his wife.

Bait said the gunmen barged into the house at around 1 am Monday and shot the victims.

All the victims died from gunshot wounds to the head.

The gunmen, however, spared the lives of the couple's two children aged 10 and 13, respectively. Police have already taken them into protective custody.