Several Philippine men sprayed houses in a farming village outside Manila with bursts of automatic weapon fire, killing nine people, most of them sleeping children, police said on Monday.

Police had earlier suspected a solitary gunman was responsible for the shooting near Calamba town on Sunday night, but regional police chief Ricardo Padilla told Reuters several men were involved and that an old feud was believed to be the motive.

"We have received information that this could be a revenge killing because of a long-standing family feud," Padilla said.

Superintendent Nestor de la Cueva, the town's police chief, said a former soldier was being questioned after an empty M-16 magazine found near the crime scene bore his name.

"We have invited him to police headquarters," de la Cueva told reporters, adding the man had denied any knowledge about the shooting.

Police said the gunmen escaped after the shooting. Five of the dead were children.

At least five people were wounded, police said, adding that the victims were all from one extended family.

The shooting comes two days after gunmen killed 10 employees of a bank in the nearby town of Cabuyao and emptied its vault. Police estimated up to 15 million pesos (over $350,000) was taken.

Nine of the dead were found lying on the floor of the branch while one man succumbed in hospital of gunshot injuries in the head.

No arrests have been made.