Tasnim � Iran on Friday handed over 19,000 Pakistanis arrested for crossing the Iran-Pakistan border illegally in 2017, an official said.

Those arrested had entered Iran through unmanned routes scattered along the 900-kilometer border with the country, the Pakistani security official said, speaking on the condition of anonymity, Pakistan Today reported.

The official added that a large number of the migrants were from the districts of Mandi Bahauddin, Gujrat, Sialkot and other areas of Punjab province.

He added that only a handful of them were able to reach Europe while the others were arrested soon after crossing into Iran.

The official further said that Iran has constructed a 64-kilometer wall to stop free cross-border movement of people, adding that human smugglers instead used less-traveled routes in Mashkail, Mand-Bilo Turbat and Panjgoor to enter the Islamic Republic.

Many of such illegal immigrants who had managed to reach Iran were arrested in Turkey and Greek early this year and were deported to back to the country. A group of 27 illegal immigrants who were detained in Turkey were deported by air to Islamabad early May.