The scene unfolds not in a church but in the basement of a small shopping centre a short walk from the vast esplanade of Portugal's Fatima shrine, one of the Catholic Church's most visited pilgrimage sites.The gathering was part of a series of monthly so-called "exorcism retreats" held in Fatima that have raised concerns among Catholic authorities, who say they operate outside official Church oversight by self-styled religious figures and risk exploiting vulnerable believers.On a recent Saturday, more than 100 people waited for the moment when Francisco Marques, 27, would start laying his hands on participants one by one.Wearing a black cassock and a Roman collar, Marques cuts the figure of a traditional Catholic cleric. But neither the Vatican nor local Church authorities recognise his ministry, which was founded in 2006.

The monthly exorcism retreats are held in the basement of a small shopping centre near the sanctuary of Fatima in Portugal © PATRICIA DE MELO MOREIRA / AFP

Marques placed both hands on their foreheads, concentrating silently.Some participants -- mostly women -- immediately fall backwards into the arms of attendants standing ready behind them before being lowered onto mats spread across the floor."You get a great feeling of peace. It's a liberation. I leave here cleansed, with a lighter soul," Lurdes Ramisio, a 56-year-old nurse, told AFP at the retreat."I feel he has a power. His hands transmit a power to me," she added.'Driving out demons'The sessions are organised by Marques and members of his family with the support of Salvatore Micalef, an Italian who presents himself as his bishop."When I met Francisco, I saw above all that he had the gift of driving out demons," Micalef told AFP. "I therefore issued a decree authorising him to be an exorcist."Exorcism is the ancient practice of driving out demons or evil spirits from a person or place they are thought to possess.