Muslims in Cardiff on residents fighting with ISIS in Syria
27 June 2014 Last updated at 10:58 BST
Young Muslims from the Yemeni community in Cardiff have been speaking about the men who are thought to have been radicalised by the militant group Isis (Islamic State in Iraq and Levant).
"Whoever is doing this is obviously targeting young boys because they feel like they can talk to the them and fill them with whatever they want them to think." Haifa Shamsan told the BBC.
Nasser Muthana and Reyaad Khan, both 20 and from Cardiff, are believed to be among 500 Briton fighting in Syria for the militant group.