It came as no surprise to Husamuddin Meyer that the gunmen who terrorized the French capital last week were likely radicalized in prison. For the past six years, the imam has been working with Muslim prisoners in the southwestern German city of Wiesbaden.

"I have to make it clear from the outset that when you go inside, you definitely don't get the impression that these are all people who are close to carrying out an attack," he told German public broadcaster ZDF. "But when you watch the news about attacks around the world, often the people who are used to carry out such attacks come from this milieu, and that doesn't surprise me at all."

When Meyer visits inmates he prays with them, counsels the group on religious matters and holds discussions about Islam. The imam, who has a large beard and wears a turban in his home of Wiesbaden, says while his audience identifies as Muslim, many often hold radical views or know very little about their religious roots.

"My job isn't to argue with radicals. I see my job as acting to boost the self-esteem of these young people," he said. "This is the most important thing, because if someone has no hatred and no more anger within themselves, then the risk of them carrying out a crime is generally lower than before."

Voice of authority

Terrorist attacks, such as the shootings in Paris, as well as the actions of groups like "Islamic State" (IS) - which the imam calls the "anti-Islamic State" - often come up in their discussions. Meyer says many of his charges don't believe the media, or think the reports are propaganda. As such, he says they are eager to hear clear statements from a trusted religious leader.

"When they hear someone in a position of authority speak clearly about it, then some are reassured, and there'll often be questions like, 'So and so has said that it's acceptable to kill someone who insults the Prophet,' and then I can say: 'No, that is absolutely not allowed.' And many find that reassuring because most of them have very little idea about their religion," he explained in the ZDF interview.

Meyer himself is a convert to Islam. Born Martin Meyer, he grew up in a Protestant German family in the rural Odenwald region. When he finished high school, he decided to travel across North Africa on a motorbike. He says the experience fundamentally changed his outlook and his religious convictions.

'Looking for a new purpose'

The Islamic scholar describes his religion as peaceful - in no way linked to violence or hate - which is why he finds the rise of Salafism, and its emergence in prisons, troubling. In Germany, Salafism is typically used as an umbrella term for extremist interpretations of Sunni Islam that have been growing in popularity in the country, including in the Wiesbaden area.

Meyer is one of the few clerics working with prisoners, and since he started in 2008, his counseling has gradually taken on a more preventative focus. While Christian chaplains are often on hand for prisoners in most German jails, it's not common practice for an imam to be employed.

Authorities believe young inmates are particularly prone to convert to radical Salafism, and that a small number of them are willing to use violence to achieve their goals. The majority of young men taken in by the scene have migrant backgrounds and seek a sense of belonging.

Meyer adds they are often marginalized, and are "looking for a new purpose in life," which, he says, can be dangerous when combined with extremist ideologies.

"If they can then be persuaded that they can move from the lowest rank in society to the highest, and become a hero, then there's a high potential for violence."