Witches haunt Kinshasa, the Democratic Republic of Congo's violent capital. With pinched faces, bloodshot eyes and swollen bellies, they are horrifying to see; plaguing the city's streets by day, and retiring when nights falls to stinking graveyards and typhus alleys. And all of them are children.
Olivier, a nine-year-old witch, sighs, making a half-chewed, blue plastic crucifix bobble against his tummy. He knows his mother has died, but not why he has been blamed. 'I'm not a sorcerer,' Olivier whispers, his thin skin gleaming with the tell-tale sheen of Aids. 'I didn't cast any spells.'
Three years ago his mother succumbed to the virus marauding through Kinshasa's slums, leaving him an orphan. An uncle took him in, but with five children of his own to feed Olivier's was one mouth too many. Within a week he resorted to another phenomenon raging through Kinshasa's slums, accusing the child of witchcraft and casting him onto the streets.
Ever since, Olivier has been scavenging for survival, begging for scraps in Kinshasa's markets, or for a few francs in its fume-filled traffic. Last year he went back to his uncle seeking forgiveness. 'He said that he'd burn me alive if he saw me again,' Olivier said.
Olivier's plight is all too common in war-ravaged Congo. According to Save the Children, of Kinshasa's estimated 30,000 street-children, virtually all have been abandoned by their families, having been accused of witchcraft.
There are many possible proofs of their magicking. Death or disease in the family are the most common: unsurprisingly, where one in five adults is infected with HIV/Aids. But at a refuge for street-children in Kinshasa's Matonge slum, urchins such as Olivier also cite lost jobs, failed crops or bad dreams as the proof of their guilt.
According to Save the Children, a recent drop in diamond prices in the southern mining town of Mbuji-Mayi saw hundreds of alleged child sorcerers cast out into the streets, while in Kinshasa, as the average annual income slips towards £50, the number of street-children has doubled in four years.
'Congolese have always believed in witchcraft,' said Father Jacques Bakewma, a Jesuit priest running Matonge's Centre Monsignor Munzihirwa refuge. 'But, traditionally, we identified only old men and women as witches. Now we are turning on our children. Whatever anyone says about African culture, this is just a convenient way of getting rid of unwanted children.'
Bewildered new arrivals at Bakwema's refuge invariably claim to be sorcerers, he said. 'But after a day or two they say they don't know why they were accused. These are just scared children, rejected children, innocents.'
None more so than Olivier. The finger of suspicion was raised against him, he said, because of his habit of praying besides his mother's sick-bed.
The evidence against Ibrahim, 10, and his brother Yves, nine, is hardly more damning. When their mother died - also of Aids - the brothers were put in the care of an aunt, who neglected to feed them, and then attributed their emaciation to witchcraft. 'It wasn't true, we were thin because we were hungry,' protested Ibrahim, examining his orange flip-flops with the grave aspect of a child with the worries of a man. 'I'm not a witch,' said Yves, a tiny child with huge hands. 'Witches exist, but we're not witches.'
Whenever a new child arrives at the refuge, Bakwema tries to trace his or her family, then persuade them to take them back. But he rarely succeeds: 'These people are genuinely terrified. They are convinced that their son or their daughter can turn into a cat or kill people with curses.'
Joel, 12, was accused of witchcraft after his grandfather dreamt he was trying to kill him. He was taken for exorcism at one of the Christian sect churches mushrooming in Kinshasa's slums.
'They beat me until I said I was a witch. They locked me in a box for a long time,' said Joel. 'Then they let me out, and said I wasn't a witch any more.'
Joel's grandfather paid the cult's fee - a bag of cement - but still refused to take the boy back. So for two years Joel has been sleeping in the street outside his family hut, begging food from his terrified relatives.
According to Bakwema, it could have been worse: many children barely survive their exorcism. 'These people torture children in the name of religion,' he said. 'They beat children, make them vomit, abuse them. It's a revolting trade.'
One practitioner is Prophet Onokoko, a self-styled Christian minister. His preferred method is to induce child witches to 'vomit up the devil' and, with 230 children on his books, demand for his services is high. In his shack-like church, Onokoko displays examples of 'devils' sicked up so far: a whole prawn, a shell in the shape of a horn, and even two barbel fish.
'These came out of the mouths of children who had spirits,' he said.
No one in Kinshasa's malodorous streets, not poor hawkers or smartly dressed government workers, seems doubt to doubt the truth of child sorcery.
Save the Children's Mahimbo Mdoe is a rare dissenter. 'As far as we're concerned what's going in that organisation is simply child abuse,' he says of Onokoko's church. 'Children are made to vomit up things that have been inserted into them.'
Yet the true calamity may be yet to happen. For, to many worried observers, it is the first clear sign that the African extended family system, a communal support system whereby orphans are adopted and war refugees taken in, is crumbling.
'The capacities of Congolese families and communities to assure basic care and protection for their children seem to be breaking down,' said Save the Children's Javier Aguilar Molina, who is carrying out the first rigorous research into the child-witch phenomenon. 'This will have terrible consequences.'