In addition to the American rapper from Minneapolis recently killed in the bloody fighting in Syria , nearly a dozen former residents of Minnesota's Twin Cities have left their homes to take up arms with extremist rebel groups in the Middle Eastern nation, U.S. officials told ABC News.Earlier this week the White House confirmed the death in Syria of Minnesotan Douglas McAuthur McCain, who records show was born in Chicago but was schooled in Minneapolis. An opposition group in Syria, the Free Syrian Army , claimed McCain was fighting with ISIS , a brutal terrorist organization that recently executed American journalist James Foley on camera. The FSA also claimed another American ISIS member had been killed in recent fighting.Representatives for several U.S. agencies said they could not confirm that a second American had been killed, but there are scores of U.S. nationals in the line of fire. Other top U.S. officials have previously said more than 100 Americans have joined the fighting in Syria - nearly a dozen of them from the Twin Cities alone, as two U.S. law enforcement officials told ABC News Thursday. And a community leader said at least one who left for Syria recently is a teenage girl.Kyle Loven, the FBI 's Chief Division Counsel in Minneapolis, said residents traveling to Syria is a "relatively recent dynamic," but still only an "evolution" of young disaffected Minnesotans leaving their homes to fight and die with extremist groups abroad."The phenomenon began in 2007 with the young Somali men traveling from Minnesota to Somalia," Loven said. "In Somalia, it started as a nationalistic call... [but] we've now seen where some individuals perhaps are not interested or not inclined to travel to Somalia, [they] start to branch out to other hot spots around the globe, obviously Syria being among them."The problem of Americans from Minneapolis traveling to Somalia to join the al Qaeda group al-Shabab became such a concern to U.S. officials that the Justice Department launched the multi-year law enforcement mission Operation Rhino , dedicated to investigating "a pipeline that supplies men" from Minneapolis to Somalia. The effort, which tracked some 20 suspected American jihadists, resulting in the conviction of several American ex-al-Shabab members.One of the young men caught up in the initial wave of terror recruits was Troy Kastigar, who turned out to be an old high school classmate and close friend of Douglas McCain's."If you guys only knew how much fun we have over here - This is the real Disneyland. Come here and join us," a bearded Kastigar says from Somalia in a video posted online by al-Shabab after his death in 2009.Mohamud Noor, a community leader in Minneapolis, told ABC News today that the young men going to fight in recent months for ISIS, which is a rival of al Qaeda's, and those who joined al-Shabab before "have the same characteristics.""They are young men who are vulnerable, who have been taken advantage of because of their situation," Noor said. "This is a youth who has lost direction, who has no hope in life, and the only way they can find [it] is to find other means of living."Another community leader, Abdirazak Bihi, said, "As recently as a week ago, a young girl was recruited along some others, and was sent to Syria and called her family from Syria a couple days ago.""Yes, people are recruiting, there are recruiters here," Bihi said.But Noor acknowledges that that doesn't explain why so many are specifically being recruited from his city, and says that one reason so much focus is on the Twin Cities is because there is a large "newly-arrived" immigrant community, with many Somalis and Middle Easterners, and because the community isn't shy about reaching out for help when someone does disappear, possibly into battles a world away.Loven said that al-Shabab's previous success in recruiting Minnesotans may have shown the area's disaffected youths to be particularly susceptible to the jihadist propaganda. Earlier this week, for instance, al-Shabab released a recruitment video online that specifically called for those living in Minnesota to come join their fight."We're taking this very seriously," Loven said. "We don't want to see our young people from Minnesota be attracted to this type of propaganda, end up in foreign battlefields, only to be injured, killed or what have you. That's a concern not just for law enforcement, but for all people here in Minnesota."