A teenager begged to die after being tortured by relatives wielding hammers, pliers and chisels who were convinced he was a witch, a court heard on Thursday.
Kristy Bamu was subjected to a "prolonged attack of unspeakable savagery and brutality" by his older sister and her partner. The 15-year-old had suffered 101 injuries by the time he died on Christmas Day in 2010, jurors heard.
Kristy's brother-in-law Eric Bikubi his partner Magalie Bamu, both 28, forced Kristy's other siblings to join in with the horrific torture, according to prosecutors. Kristy's face and head were covered in deep cuts and bruises and his teeth had been removed, the court was told.
Brian Altman QC, prosecuting, accused Bamu and Bikubi of beating, torturing and drowning Kristy after they accused him of witchcraft and sorcery.
"Despite her own siblings' denials that they were sorcerers, Magdalie Bamu joined her boyfriend in repeating these fantastic claims and participating in the assaults," he told the court.
"They beat the three of them, refusing to let them eat, drink or sleep for days while the punishments being meted out became increasingly violent, with them using many implements found in the flat as weapons of torture."
Bamu and Bikubi forced Kristy's other siblings to join in with the brutal beatings before they were all placed in the bath and hosed down in cold water by Bikubi, according The Press Association.
Altman describing how Kristy soon became the "focus" of Bikubi's attention.
"In a desperate attempt to prevent any further suffering, [Kristy] and his two sisters were eventually made to admit to being sorcerers.
"Wickedly, the defendants also recruited sibling against sibling as vehicles for their violence.
"In a staggering act of depravity and cruelty, they both forced the others to take part in the assaults upon Kristy.
"The children had no option other than to do as they were told, or risk the same violence to themselves.
After Kristy begged to be left to die, Bikubi put him in the bath. The teenager was too badly injured and exhausted to keep his head above the water, the jury was told.
"It was only when [Bikubi] realised that Kristy was not moving that he stopped what he was doing and pulled him from the water. By then it was too late," added Altman.
The prosecutor said Kristy had 101 injuries and died from a combination of being beaten and drowning.
Paramedics tried to save him but he was already dead.
In the blood-covered living room, police found Kristy's brothers and sisters - brothers Yves, 22, and a 13-year-old, and sisters Kelly, 20, and an 11-year-old.
The youngsters had arrived from their home in Paris to spend the festive season with the couple.
Kelly said their holiday turned sour when Bikubi accused Kristy, herself and their younger sister of "being witches or sorcerers - practising witchcraft - and adversely influencing his three-year-old son".
"All were standing in the living room, hysterical, terrified and soaking wet. None of them spoke any English. Both girls appeared to be injured," Altman told the Old Bailey.
Kelly told a paramedic who attended the scene a "tale of horror", according to Altman. The 20-year-old pointed to a metal bar with which she was beaten and a hammer which had been used to hit her brother Kristy in the mouth.
Despite several calls being made to their home in Paris, the children's parents had not realised what was happening.
Bikubi threatened Kelly with a knife when she spoke to her father, forcing her to make up a story.
"He thought he had sent his children on holiday, not to a torture chamber," added Altman.
Both defendants, of Hathaway Crescent, Newham, east London, deny murder. Bamu also denies two charges of causing actual bodily harm to her sisters. When asked by her sister Kelly why she would not protect them, Bamu had simply said "they deserved it and that she had no pity for them", the court was told.
Previously in 2008, Bikubi had accused family friend Naomi Ilonga of being involved in witchcraft and had forced her to cut her hair short to try to purge herself.
Altman said Bikubi has admitted manslaughter on the grounds of diminished responsibility, but this was rejected by the prosecution who say the couple carried out "the very deliberate murder" of Kristy.
The jury was told that in the Democratic Republic of the Congo, where the defendants are originally from, witchcraft or sorcery, called kindoki, is practised in Christian churches.
But if it is taken out of the church's control "it may take on a feral and indeed evil character, as we suggest it did here", Altman said.
The case continues.