Police now say 19 people were killed and at least six others gravely wounded when armed men rampaged through a village in northern Nigeria, shooting people and slashing them with machetes.

Local police said a group of 150 assailants descended on the village of Lingyado in Zamfara state knocking on people's doors and attacking them.

The motive for the attack remains unclear. However, police said they believe the assault was retaliation for an attack in August on another village in the area.

Authorities have sent troops to Lingyado in an effort to restore order.

Communal clashes stemming from cattle rustling or political differences are not unusual in Nigeria.

The radical Islamist sect Boko Haram has been blamed for dozens of attacks in Nigeria's north, but police gave no indication the group was involved in the deadly raid.