In an interview with state-run news agency IRNA on Friday, Gholam Hossein Ismaili, said that the prisoners have been sent to concentration camps in Isfahan and Khorasan Razavi provinces.
Based on local media, there are 217 thousand prisoners in Iran with half of them for drug charges.
Head of the State Security Forces in Iran, Ismail Ahmadi Moqaddam, had previously said that the aim to operate 11 concentration camps was to punish those involved in drugs.