The detention took place following the Ankara-led operation against the Gulen movement in the Balkan region, the Anadolu news agency said, referring to its sources.
According to the agency, the detainees are accused of helping FETO members flee Turkey to countries like the United States.
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The detainees — Cihan Ozkan, Kahraman Demirez, Hasan Huseyin Gunakan, Mustafa Erdem, Osman Karakaya, and Yusuf Karabina — were brought back to Turkey, where they are all wanted as FETO fugitives, the agency added.
Since July 2016, Ankara has arrested thousands of public servants, military personnel, education workers, activists and journalists over suspected links to Gulen and his movement.