Mohsen Safaei, an official of the Islamic Republic, announced that of the 12 districts of South Khorasan, only two districts of Khusf and Birjand are allowed to give residency to Afghans.
Safaei, director of aliens and foreign immigrants of South Khorasan Governorate, said that Afghans are prohibited from staying in 10 other districts of the province.
In an interview with Mehr News Agency published on Thursday, he added, "There are more than 10,000 foreign nationals residing in South Khorasan."
According to him, most of the foreign citizens in South Khorasan are Afghans.
Safaei also reported that about 1,700 students and 600 foreign students are studying in South Khorasan.
Safaei added that buying and selling real estate to "unauthorised Afghans" is prohibited.
The official warned that "unauthorised Afghans" will not be given any kind of assistance and that they will be dealt with and deported from Iran as soon as they are identified.
Iranian officials have recently said that they are closing the country's borders to prevent the illegal entry of migrants, the movement of terrorists and drug traffickers.
About a week ago, Sirous Amanollahi, a commander of the Iranian army's ground forces, said that the closure of borders in Khorasan Razavi, South Khorasan and Sistan and Baluchestan would be completed in three years.