"Isil hast turned terrorist recruitment and Radicalisation effectively into a mass product," said Koehler.
The Islamic State uses songs, videos and even games to spread its propaganda message on the Internet. "The main narratives presented in Isil's propaganda is a very condensed but nevertheless highly emotional and effective way to connect to various different biographical backgrounds and age groups," Koehler said.
Those who might be influenced most easily through such propaganda are children - a group rarely included in the counter-Radicalisation programs that have become common in Europe. Experts say that further attacks could be prevented through dedicating more money to such prevention programs to widen their scope. "If children feel like they are in good hands they might not be so easy to manipulate," Susanne Schroeter, an Islam and Conflict Studies professor at Frankfurt's Goethe University, was quoted as saying.
In other countries, including Britain, similar initiatives have recently gained ground. In west London, for instance, a soccer club teaches children about gender and religious equality to make them less susceptible to Islamic State propaganda. The club also trains volunteers to spot the first signs of Radicalisation among its members.
In total, 3,300 members nationally have played at the club since the project was established last year. Open to girls and boys ages 10 to 17, it has attracted boys and girls from across the British capital and has about 300 members. Some of the younger residents struggle with feelings of isolation and loneliness, and have questions about their identity, their supervisors said.
Muad Hussein, a 13-year-old player of Somali heritage, explained that he preferred to focus on winning matches, rather than discuss Radicalisation. "It doesn't matter what religion or ethnicity someone has. Here, we are all one tough family," he said. The club offers a safe haven that is free of charge, volunteers said. Soccer sessions are complemented by discussions about fairness and democratic values.
Participation in the project, however, has proven more difficult with girls. "Sometimes, the girls left training and guys came up to them asking: 'What are you doing there?' " volunteer coach Simon Agboola said. "Some families were not okay with them playing soccer." Including parents in counter-Radicalisation programs designed for children remains a main obstacle, organisers acknowledged.
Following the failed nail bomb attacks in Germany, authorities are now also exploring whether the boy's parents were aware of his alleged plans and whether they might have contributed to a possible Radicalisation.
Amid growing concerns over children being targeted by Isis, German de-Radicalisation expert Daniel Koehler has put a particular emphasis on family counselling. "Family and friends are the ones picking up a Radicalisation or more broadly a change into a negative direction first."
"They are our first line of defence and they are the ones best suited to intervene at an early stage," he said. The difficulty, however, is to convince parents of 12-year old children that their sons of boys may be targeted by the Islamic State in the first place.