Militiamen killed 12 people in a night raid on a village in eastern Democratic Republic of Congo near the shore of Lake Albert, a local human rights group said on Tuesday.

The group and an army spokesman blamed the attack on CODECO, one of many militias operating in Congo's conflict-ridden east.

CODECO's fighters are drawn mainly from the Lendu farming community, which has long been in conflict with Hema herders. The group could not be reached for comment.

"We have been alerted that CODECO militiamen killed people again in the Bahema-Nord chiefdom. Our forces are on the ground pursuing the enemy," said Jules Ngongo, Congolese army spokesman for Ituri province. He did not give a death toll.

The provisional toll is 12 dead and two injured, said Dieudonne Lossa, president of the Ituri province civil society chapter, which monitors killings.

In the worst attack so far this year, CODECO killed around 60 people at a displaced persons camp in February.

Congo's government declared martial law in Ituri and neighbouring North Kivu province more than a year ago in an effort to quell the violence, but deadly raids have surged since then.