DR Congo security forces have killed 31 armed assailants in clashes around Lubumbashi, the country’s second-largest city, a human rights group said Sunday, denouncing the action as human butchery”.

The NGO, Justicia, said that seven attackers and one police officer were killed in Lubumbashi on Saturday, 13 militia men were killed in Likasi, nine in Kasumbalesa on the border with Zambia and two in Bunkeya, another town in region which is rich in cobalt.

While denouncing what it described as an “destabilisation attempt” by the attackers, Justicia also hit out at the army for “opening fire without warning” on the militia men who were more lightly armed, some just carrying knives.

This, the group said, amounted to “human butchery”.

Congolese police had said on Saturday that the militia men, loyal to former warlord Gedeon Kyungu Mutanga, were “forced back by police and the armed forces”.

Mutanga had left his home in Lubumbashi during the fighting, police said, without specifying whether the residence had been placed under surveillance.

The Congolese warlord was jailed for life in 2009 for crimes against humanity, war crimes, insurrection and terrorism.

But he broke out of prison in September 2011 and made a dramatic public appearance in Lubumbashi in October 2016 during an official ceremony given in his honour.

France said it had frozen Mutanga’s assets at the start of 2018.

Lubumbashi was placed under lockdown for two days last Monday and Tuesday after two suspected case of coronavirus were reported. However, both cases tested negative to COVID-19.