According to a charge sheet dated 20 May but which public prosecutors in Lourinhã have only now allowed journalists to consult, Leitão faces 542 rape charges, six of child pornography and another of serious threats of violence, assault and privacy intrusion.

The charges relate to events that took place between 2009 and and 18 July 2010, when Leitão was detained by the Polícia Judiciária force as a homicide suspect in an investigation into the deaths of thre young people. In 2012 he was found guilty of murder and sentenced to 25 years in prison.

The court found that Leitão, who worked as a scrap merchant, lived with various young people aged between 14 and 17, presenting himself as a friend who would take them out, pay for meals and drinks for them, and gave them mobile phones.

He would tell people that he had supernatural powers, staging sessions at which he purported to speak with the spirits of the dead, and performed magic tricks with light and recording equipment that frightened the young people.

"The victims were led to have an adulterated perception of reality, in which they believed and to which they subjected themselves, allowing the accused to manipulate them," the new charge sheet states.

Among other things, Leitão led his victims to believe that negative "copies" of human beings existed that were bent on their destruction. To save them and eliminate these copies, he told the young people, they would have to "attacin certain levels of energy in their body".

Once he had won them over, Leitão would take them to his house in the village of Carqueja, near Lourinhã, in Lisbon district, where they were persuaded to avoid the terrible consequences of such phenomena by allowing themselves to be subjected to "injections of energy", which, according to the charge sheet, would be transmitted from the body of the accused to that of the victim in the form of sexual relations.

For fear of the consequences, the youngsters agreed, and were then obliged to meet a "timetable of sexual practices", the charge sheet states, adding that several times Leitão also called for the youngsters to have sex between them, as he watched.

To other youngsters Leitão would give drinks with "medicines or similar substances", leaving them unconscious for periods that enabled him to physically abuse their bodies. Several times he used video cameras to film these practices, without the victims' consent.

At one point, another three people were suspected of having released the videos produced by Leitão, but public prosecutors ended up shelving that part of the investigation for lack of evidence.

Complaints were first made about the incidents in 2009, but the investigation was shelved. It was reopened after a search of Leitão's house and fresh allegations at a time when he was being investigated for the three alleged homicides.

In the meantime he was also found guilty of possessing an illegal weapon and of forgery, simulation of a crime, and receiving stolen goods.

The case is to be heard by the court of north Lisbon, in Loures.