The incident occurred on Saturday afternoon in the village of Mugerwa, about 15 kilometres (nine miles) from the city of Goma, in circumstances that remain unclear.

One security official, who requested anonymity, said that soldiers had a quarrel with so-called Wazalendo militiamen which ended in an exchange of fire.

"They shot at each other in this misunderstanding and there are six dead and nine wounded," the security official said.

The incident comes after clashes with M23 rebels erupted last month, breaking several months of relative calm in the region.

A Tutsi-led group, the M23 has seized swathes of territory since launching an offensive in late 2021, driving over one million people from their homes.

The current fighting pits the M23 rebels on the one hand against the Congolese army and loyal militias -- known locally as 'Wazalendo' -- on the other.

Details of the recent shoot-out between the soldiers and Wazalendo fighters are hazy.

Mambo Kawaya, a civil-society leader near Goma, told AFP that six people had been killed and ten wounded.

Adolphe Muhire, a member of the DRC's civil protection service near Goma, said that one soldier, one policeman and four civilians had been killed.

"The toll is still provisional," he said.

Three other sources gave similar death tolls, although they cited different figures for the number of people injured in the incident.

AFP was unable to independently confirm the details of the attack.

A spokesman for the Congolese army in Goma was not immediately available for comment.

Militias have plagued eastern DRC for decades, a legacy of regional wars that flared in the 1990s and 2000s.

Several Western countries, including the United States and France have concluded that Rwanda backs the M23. Kigali denies the claim.