Five were given 19-year terms, while the sixth defendant received a nine-year prison sentence.
Tajik media quote an aide to the prosecutor in Sughd region, Asadullo Urunov, as saying the defendants belong to the banned Islamic Movement of Uzbekistan (IMU).
They were convicted on charges that included creating a criminal and extremist group with a terrorist agenda, inciting religious and religious hatred, the illegal possession of weapons, and polygamy.
Central Asian governments claim the IMU, which was believed to have been destroyed at the start of the U.S.-led military campaign in neighboring Afghanistan, is showing signs of renewed activity.
(Avesta, Asia-Plus)
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