PESHAWAR: Pakistani officials reported that more than 100,000 Afghan nationals had returned to their Taliban-ruled homeland in the past two weeks, as a deadline for undocumented immigrants to leave Pakistan was set to expire by the end of Wednesday.

A senior official in Khyber Pakhtunkhwa, a northwestern province bordering Afghanistan, gave the number for people who had left via the main Torkham border crossing.

"Some of them have been living in Pakistan for more than 30 years without any proof of registration," Deputy Commissioner Abdul Nasir Khan said.

An as yet undetermined number have also gone back via Chaman, the border town in the southwestern province of Balochistan.

Earlier in October, Pakistan warned it would expel all undocumented immigrants, including hundreds of thousands of Afghan nationals, who remained in the country after Nov. 1.

The government said an operation to round up and expel people would start on Thursday.

More than four million Afghans are living in Pakistan, of which some 1.7 million are undocumented, according to government estimates. Many are families who fled during decades of conflict that Afghanistan has suffered since the late 1970s, while the Taliban takeover following the U.S. withdrawal in 2021 led to another exodus.

Taking its hardline stance, the Pakistan government has said Afghan nationals have been behind militant attacks, smuggling and other crimes in its territory.

Kabul dismissed the accusations and rights groups protested, asking Pakistan to reconsider.