At least 100 people, mostly unarmed civilians, have been killed in a wave of horrific attacks in southern Democratic Republic of Congo.
General Nzambe showing pictures of the mutilated bodies of his soldiers
One survivor told the BBC's Arnaud Zajtman in Lubumbashi that militiamen drained the blood of those they killed and put it into bottles.
"After they had cut off the sexual organs, they walked away with them. They took the victims' blood in flasks," said Claude Panza wa Losol, 22, nursing a bullet wound in his arm in the town's Don Bosco hospital.
The military commander of Katanga province, General Alengbia Nzambe, showed our correspondent pictures of the bodies of seven soldiers who had their faces and genitals cut off.
Our correspondent says that many fighters believe that using the body parts of their victims to make charms will make them more powerful.
The attacks are blamed on a militia led by General "Chinja Chinja" or the Ripper.
Congolese military officials say that he is the last remaining militia leader in the north of Katanga province who is unwilling to integrate into the new Congolese army.
After five years of war, former rebel forces are being merged into a new united army under a peace deal.
Some 10,000 United Nations peacekeepers are in DR Congo to monitor a peace accord but they have not been sent to the scene of the atrocities.
UN spokesman Hamidoun Toure said that verifications were being made.
General Alengbia Nzambe has said that he will neutralise the Ripper.
But an aid worker in the region said that given the atrocities which were committed by the Ripper, he feared that a response from the Congolese army could generate more bloodshed.