Large numbers of Afghans crammed into trucks and buses in Pakistan on Tuesday, heading to the border to return home ahead of the expiration of a Pakistani government deadline for those who are in the country illegally to leave or face deportation.

The deadline is part of a new anti-migrant crackdown that targets all undocumented or unregistered foreigners, according to Islamabad. But it mostly affects Afghans, who make up the bulk of migrants in Pakistan.

The expulsion campaign has drawn widespread criticism from U.N. agencies, rights groups and the Taliban-led administration in Afghanistan.

Pakistani officials warn that people who are in the country illegally face arrest and deportation after Oct. 31. U.N. agencies say there are more than 2 million undocumented Afghans in Pakistan, at least 600,000 of whom fled after the Taliban takeover in 2021.

Human Right Watch on Tuesday accused Pakistan of resorting to "threats, abuse, and detention to coerce Afghan asylum seekers without legal status" to return to Afghanistan. The New York-based watchdog appealed for authorities to drop the deadline and work with the U.N. refugee agency to register those without papers.

Although the government insists it isn't targeting Afghans, the campaign comes amid strained relations between Pakistan and the Taliban rulers next door. Islamabad accuses Kabul of turning a blind eye to Taliban-allied militants who find shelter in Afghanistan, from where they go back and forth across the two countries' shared 2,611-kilometer (1,622-mile) border to stage attacks in Pakistan. The Taliban deny the accusations.

"My father came to Pakistan 40 years ago," said 52-year-old Mohammad Amin, speaking in Peshawar, the capital of the northwestern Khyber Pakhtunkhwa province that borders Afghanistan.

"He died here. My mother also died here and their graves are in Pakistan," said Amin, originally from Afghanistan's eastern Nangarhar province. "We are going back today as we never tried to register ourselves as refugees with the U.N. refugee agency."

"I am going back with good memories," he told The Associated Press, adding he planned to head to the Torkham border crossing later Tuesday and that he'd asked the Taliban government for help to start a new life.

Nasrullah Khan, 62, said he'd heard the Taliban are considering helping Afghans on their return from Pakistan. He said he was not worried by the prospect of Taliban rule but that it was still "better to go back to Afghanistan instead of getting arrested here."

Pakistani officials said the Torkam and Chaman border crossings with Afghanistan will remain open beyond their daily 4 p.m. closure to allow for those who have arrived there to leave the country.

More than 200,000 Afghans have returned home since the crackdown was launched, according to Pakistani officials. U.N. agencies have reported a sharp increase in Afghans leaving Pakistan ahead of the deadline.

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Pakistan has insisted the deportations would be carried out in a "phased and orderly" manner.

A Taliban delegation traveled to Nangarhar Tuesday to find solutions for Afghans returning through the Torkham border.

Sayed Ahmad Banwari, the deputy provincial governor, told state TV that local authorities are working hard to establish temporary camps.

Banwari said that families with nowhere to go can stay in the camps for a month until they find a place to live.

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The crackdown has worried thousands of Afghans in Pakistan waiting for relocation to the United States under a special refugee program since fleeing the Taliban takeover. Under U.S. rules, applicants first had to relocate to a third country — in this case Pakistan — for their cases to be processed.

A U.S. diplomat, who spoke on condition of anonymity to discuss the policy, said Washington's priority was to facilitate the safe and efficient resettlement and relocation of more than 25,000 eligible Afghans in Pakistan to the U.S.

Even before the Pakistani campaign was announced, Washington had asked Islamabad "to ensure the protection of Afghan refugees and asylum seekers, including those in the U.S. resettlement and immigration pipelines," the diplomat said. "We are in the process of sending letters to those individuals that they can share with local authorities to help identify them as individuals in the U.S. pipeline".

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The applicants often protest in Pakistan against the delay in the approval of their U.S. visas.

Afghanistan is going through a severe humanitarian crisis, particularly for women and girls, who are banned by the Taliban from getting an education beyond the sixth grade, most public spaces and jobs. There are also restrictions on media, activists, and civil society organizations.

Jan Achakzai, a government spokesman in Pakistan's southwestern Baluchistan province, said on Tuesday that anyone who is detained under the new policy will be well treated and receive transport to the Chaman border crossing point.