The General Directorate of Prisons and Detention Centers of the Ministry of Interior (MoI) confirmed this in a statement.
The men were also found guilty of murder besides committing kidnappings in Afghanistan's western Herat province, reported the Khaama Press.
President Ashraf Ghani issued the death sentence of the convicted prisoners.
The group had also been involved in other illegal activities.
This comes after almost three years when one of the prominent gang leaders of the kidnappers Habib Istalif was hanged to death over similar charges.
