The shabby room in a one-story house in suburban Gaza was shrouded in darkness, and only the mutterings of a bearded exorcist broke the silence.
A man lay stretched on a grubby mattress, writhing, as the faith healer recited Koranic verses to chase away an evil spirit.
"Get out, you demon," the exorcist, who calls himself Sheikh Ali, threatened the spirit. "Get out or I will burn you."
There are a lot of demons to chase in this poverty-riddled Palestinian enclave, say a growing number of Koranic exorcists who have set up shop in Gaza, offering to end the torments of their sometimes highly disturbed patients.
The growth of exorcist clinics is seen by some as a sign of rising religious fervour among ordinary Palestinians. Hamas, the Islamic militant group that runs Gaza, however, is increasingly concerned that many exorcists are simply charlatans.
Nobody knows how many exorcists are here, but Hamas investigators say they uncovered 30 cases of fraud last year alone. There have also been complaints that healers are using dark magic to cast spells on their clients, and the police say they have found evidence of sexual abuses committed during these sessions.
"We caught some suspects red-handed, practicing exorcism, using magic to separate married couples and other things, under the pretext of helping people," said Lieut. Col. Abdel-Baset Al-Masri, head of Hamas's police investigation unit.
"It was all an act of deception and exploitation. Some people handed over fortunes and one woman gave all her jewellery to one of these exorcists."
The idea of demonic possession exists in many religions, and belief in the existence of demons and spirits, known as jinns, is widespread among Muslims, but many mainstream clerics doubt they can possess the human body, and disapprove of the work of the so-called Koranic clinics.
Sheikh Ali begs to differ. He says jinns can wreak havoc on human relations, driving a wedge between married couples or causing women to be infertile, and he says his work shows they can also take up residence in a human body.
"I help people. I recite the Koran to burn the evil spirit if they refuse to come out," he said. Putting the theory to practice one day last week, he read out Koranic verses for almost half an hour over his prone patient, whose face turned gradually red, the veins rising on his forehead.
"I will not hurt him," the young man said in a voice that Sheikh Ali claimed came from the jinn. The voice went on to say that it had "stormed" the victim's body three years ago, driven by the jealousy of a woman.
Sheikh Ahmed Nemir, a Hamas leader and well-known Muslim cleric, believes in the power of possession, unlike some of his peers. He says economic hardship and psychological traumas have encouraged evil spirits.
The Gaza Strip is one of the most densely populated places on earth, with more than 1.5 million people crammed into the 360-square-kilometer, or 140-square-mile, territory, shut off from the rest of the world by Israeli and Egyptian security barriers.
Sheikh Nemir said Muslims with weak faith and values were vulnerable to possession by jinns acting as the agents of hostile religions.
"The spirits are Jewish and Christians," the white-bearded cleric said.
"Spirits who claim to be Muslims are collaborators because they obey the Jewish and Christians masters." Medical experts say Gaza's jinns are what most doctors would diagnose as symptoms of psychological illness.
"People are more attached to exorcism than to therapy because exorcists have existed for centuries," said Fadel Abu Heen, a Gaza psychologist. In Gaza, he said, "psychological treatment only came into existence around the 1970s."
Recent studies have shown that up to 12 percent of people in Gaza suffer from psychological trauma caused by the conflict with Israel, economic troubles and isolation.
Colonel Masri, of the police, said opportunists had seized on human weakness to extort payment from fragile minds. To tackle the scourge, he has urged lawmakers to toughen penalties for abusive exorcists, who now risk a maximum sentence of three years in prison.
Sheikh Ali said some exorcists were themselves victims. "Some people, healers, are slaves to demons and bad spirits to help them in their work," he said, saying they needed the same help he was offering his tormented client.
The man on the mattress was a taxi driver who was suffering headaches and was unable to socialize normally because of his plight, Sheikh Ali said. After lengthy Koranic recitation, the jinn appeared ready to slink away.
"It offered to exit through the heart," he said. "It wanted to kill him." Some say the chasing of spirits is religious, while others detect fraud Poverty poses biggest challenge to stability of Syrian regime.
(Editing by Crispian Balmer)