Leaning up from the cot on the filthy floor of the hospital in Nyamasheke and holding the bandage that covered the exit wound on the back of his head, Mr Mazimpaka whispered a man's name.
"He was an Interahamwe" he said, referring to the dreaded militias that killed hundreds of thousands of people in Rwanda. "I am sure of it."
If Mr Mazimpaka's memory and the reports by United Nations military observers are correct, then it appears that Rwanda's killers have started a campaign to stage a comeback just five months after their defeat by the rebels of the Rwandese Patriotic Front(RPW).
According to UN military sources the forces of Rwanda's defeated Hutu extremist government have regrouped and embarked on a looting and killing spree that appears aimed at destabilising the country's new government.
The sources said that elements of the former government have over the last week staged successful commando-style raids on villages bordering the shores of Lake Kivu in western Rwanda, as well as in towns in the south-east.
The latter are within easy striking distance of refugee camps in Tanzania, which are well known strongholds of the former government The target of the latest attack has been the village of Nyamasheke, which sits on the tip of a peninsula jutting into Lake Kivu. UN sources say the village suffered at least six well co-ordinated attacks in the 36-hour period beginning last Thursday.
The last attack took place early on Saturday morning against Mubumbano, a small rural community near Nyamasheke.The killers selected three houses and attacked them with rifles and machetes.
Not even infants were spared, Two babies were injured by machete blows to the head, but survived. One child, his mother, father and a middle-aged woman were not so lucky.
At the weekend the neighbours and friends of those killed in Saturday's raid stood around the four mounds of dirt - three of them large enough for adults, and one perceptibly smaller, that marked the graves of the victims.
They were frightened and angry. "The bandits shot these people and then cut them with machetes. We are frightened, and we need protection," said one woman in the crowd.
Combined rifles and machete attacks are the hall mark of the Interahamwe militias, responsible for the massacres in Rwanda last April in which as many as 1 million people were killed.
UN sources and local residents say that the attackers operate in teams that infiltrate Rwanda by boat from Ijwi, an island on the Zairean side of the lake.
"The bandits come from over there," said Baltizar Seminega, a teenage boy, pointing at a valley in the island, which is visible from Nyamasheke. "They come here by boat and they steal from us and kill us."
UN officials said that although the raids seemed to be aimed at rustling cattle and looting, they believe the attacks represent the beginnings of a low-level insurgency campaign in the form of hit and run operations.
"It is clear that the attackers have good intelligence and choose their targets carefully. Many of the attacks showed a great deal of precision," one military source said. "If the aim of the former government is to try to create instability in Rwanda then it is succeeding." he added.
For months now there have been reports that former members of Rwanda's extremist government army have been training in preparation for a guerrilla war and a destabilisation campaign to avenge their defeat.
Government officials in south-western Rwanda acknowledged that RPF soldiers have engaged troops of the former regime who were trying to infiltrate Rwanda from Ijwi, but dismiss the significance of the raids. "They represent no threat at all," said Theobald Rutihunza, the governor of Cyangugu province, which encompasses Nyamasheke. "That [former government] army across the border [in Zaire] is disorganised and undisciplined. Their threat to come back here is nothing more than a wish that they have no mea ns to make come true."
In an internal report written in October the UN said that the former government forces were undergoing a reorganisation process and were expected to mount small-scale insurgency operations in the near future, probably within six months.
The report added: "The risk of such operations increases as time progresses. The size and effectiveness of future RGF [Rwanda Government Force] operations will depend on the level of outside assistance available to them."
But the south-west has not been the only area to suffer raids. At least 10 people died last Wednesday in attacks on a village near the south eastern town of Kibungo. The attackers reportedly infiltrated from Rwandan refugee camps in Tanzania .
The reorganisation, and the public desire by Rwanda's former leaders to retake their country by force, led one French relief agency, Medecins Sans Fronti`eres (MSF), to pull out of the Rwanda refugee camps last month.
At the time MSF said it was "unacceptable that the international community allows humanitarian aid to so openly strengthen and legitimise the power of leaders of a regime which organised and perpetrated a genocide".
According to a leaked document obtained by the Independent, the UN force commander in Rwanda, Major-General Guy Tousignant, said that December and January would be decisive months for the former regime. The document quotes the general as saying that if the former regime failed to live up to its promises to launch a counter attack against Rwanda around Christmas, the morale of its forces would suffer possibly an irreversible blow.