news was told they'd identified the bomber known in social media as abu harer. town. >> his attack in the north is said to have been one of the four suicide assaults that day killing dozens. as many as 100 americans are said to have joined thousands of foreign fighters taking part in training and contact with rebel groups. it's feared some of the americans may return home with combat training, bomb-making expertise and a commitment to wreak havoc here. >> i'm joined in the studio with a group providing strategic intelligence. he's a former chief for counterintelligence, a u.n. coordinator for taliban issues and author of a report on foreign fighters in syria. thanks for being here. >> thank you. >> what does your report say about the role of foreign fighters in syria, and hundreds forces. >> there's a lot of them. up to 12,000. that is mainly made up of people from the arab world. nonetheless, countries. >> where are the people coming from? the americans that are recruited, how are they going found and indoctrinated. >> a lot are finding their own way. by whatev