More than 70 men and women have been executed in the restive eastern Democratic Republic of Congo, the UN mission in the country (MONUSCO) has said.

"The reports received by MONUSCO suggest that the summary executions were allegedly committed mainly by armed groups to spread terror among the population. The majority of the victims were killed with machete," MONUSCO said in a statement on Thursday.

The killings happened in late January and early February, a MONUSCO spokesman told the Agence-France Press news agency.

They took place in the Nyamaboko villages I and II in the resource-rich northeastern North Kivu province where armed groups regularly attack civilians over ethnic or commercial disputes.

In December, MONUSCO's intervention force, whose mission is to neutralise all the armed groups active in the troubled country, boosted its presence in the area.

Government troops struck a rare and striking military success when, backed by the UN brigade, they defeated the powerful M23 rebel group in November.

Since then, MONUSCO has been focusing on going after other armed militias operating in the same region.

MONUSCO said it was in the process of verifying the information about the mass executions on the ground.

"MONUSCO shall spare no efforts to neutralize all the armed groups responsible for such acts," it said in the statement.

Meanwhile, Martin Kobler, the head of the mission, expressed "serious concern over the allegations of the gross human rights violations deemed unacceptable".

He said any person involved in such acts should face justice.