DRC army blamed ADF for the attack, but other sources say attacks may have been ethnic in origin.
Democratic Republic of the Congo politicians voted on Thursday to extend martial law in the restive east of the country for 15 days, a month after they replaced civilian authorities with military administrations in North Kivu and Ituri provinces.
Violence has been endemic in DRC’s mineral-rich eastern regions since the official end of the civil war in 2003, but insecurity has soared in the past two years.
On May 6, the government imposed a state of siege to try to end the bloodshed. Violent attacks have since continued, but Justice Minister Rose Mutombo said numerous militia fighters had surrendered and the army had seized control of new areas.
“Much remains to be done, and the recent volcanic eruption of Nyiragongo, which occurred in the middle of a state of siege, has forced the government to concentrate its efforts in dealing with this natural disaster,” Mutombo said.
The eruption on May 22 sent rivers of lava streaming through the outskirts of the city of Goma, killing at least 31 people and making 20,000 homeless, according to United Nations figures.
The state of siege also failed to prevent the killing of at least 55 people by rebel fighters on Monday, potentially the worst night of violence the area has seen in at least four years.
On Wednesday, 11 miners in the gold-rich territory of Djugu, in the northeastern province of Ituri, were killed by a local group called the Patriotic Force and Integrationist of Congo (FPIC), Mungwalu district mayor Jean-Pierre Pikilisende told AFP news agency.
Pikilisende said the rebel fighters had come to take control over the area, whose gold is mined by poor artisanal diggers.
The Kivu Security Tracker (KST), a respected NGO that monitors violence in eastern DRC, said 12 people had been executed.