DENVER - Sources tell ABC News that three teenage girls from the Denver metro area are back with their families in Colorado after they were taken into custody by the FBI in Germany. Authorities said the teens were stopped en route to Syria and planned to join militant groups.
The three girls, all under the age of 18, were persuaded to travel overseas and were in contact with someone in Germany. Someone close to them notified authorities, and the FBI tracked them down in Frankfurt, Germany, ABC News reported.
A U.S. official said the girls were headed toward Turkey en route to Syria and that investigators were now reviewing evidence, including the girls' computers.
Another U.S. official called the case "concerning" both to the community and to the country in general, according to an Associated Press report. The official said the evidence gathered so far made it clear that the girls were headed to Syria, though the official said investigators were still determining what sort of contacts they had in that country.
The officials spoke to the AP on condition of anonymity because they were not authorized to discuss the ongoing investigation by name.
The girls have not been publicly identified.
A source told 7NEWS that the two of the teens are sisters of Somali descent, and the third teen is a friend whose family is from the Sudan. The two sisters are 15 and 17 years old. The third girl is 16, ABC News learned.
Because they are minors, it is not clear if the teens will be charged. Crimes committed by juveniles are treated as acts of "delinquency" in the federal system and are not handled the same way as crimes committed by adults.
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"FBI Denver Division is aware of the situation and assisted with bringing the individuals back to Denver. The juveniles are safe and reunited with their families," FBI Denver spokeswoman Sue Payne said.
One law enforcement official told ABC News that this is part of a particular concerning trend of "disaffected youth" who are being radicalized.
The official said the teens were trying "to fulfill what they believe is some vision that has been put out on a slick media campaign" by radical groups in Syria, including ISIS, ABC News reported.
7NEWS learned the two sisters told family members that they were sick on Friday and did not go to school. They were not home when their father returned that evening and he reported them missing.
The girls' father was contacted by another parent who said his daughter was missing and that she had taken her passport. The father of the sisters said he checked and found $2,000 missing along with their passports. That's when he contacted the Arapahoe County Sheriff's Office.
The names of the three girls were entered into state and national databases as runaways on Friday.
The incident involving the three teens comes just six months after the arrest of Shannon Maureen Conley, 19, of Arvada.
Conley, a Muslim convert, was arrested April 8 at DIA after telling FBI agents she was traveling to Syria to use her American military training from the U.S. Army Explorers to aid Islamic militants waging jihad -- or holy war -- even though she knew that it was illegal, according to federal court records.
Conley was charged with conspiring to help a foreign terrorist organization and pleaded guilty last month.