The cow had been slaughtered and bags of rice purchased but young bride Wahida's nuptials were cut short when her groom was arrested on their wedding day, one of hundreds caught in a recent crackdown on Afghans living in Pakistan.

The 20-year-old now lives with her in-laws at the Afghan Muhajir aid camp in the port mega-city of Karachi but without her husband-to-be, a registered refugee. 

"We are without hope," the groom's mother, Safar Gul, told AFP. "The police took away our son. What can we do, they have the power."

Faizur Rehman, 22, was arrested "just because he was Afghan", another relative named Zulaikha said.

Afghans have poured into Pakistan in their millions during decades of successive wars, many living in aid camps with restricted access to education, healthcare and employment. 

Around 1.3 million are registered refugees and 880,000 more have legal status to remain in Pakistan, according to the latest United Nations figures.

Police and politicians have said a recent round-up targets only those without legal status and is in response to rising crime and poor regulation of immigration that is straining resources.

At least 700 Afghans have been arrested since early September in Karachi alone -- 10 times more than in August -- and hundreds more in the other cities, according to official police figures.

Afghans say the arrests have been indiscriminate.

They accuse police of extorting money and ignoring legal documents, while pointing to rising anti-Afghan sentiment as prolonged economic hardship burdens Pakistani households and tensions rise between Islamabad and Kabul's new Taliban government. 

"We have been working day and night getting people released," said Habibur Rehman, who fled Afghanistan in the 1980s during Soviet rule but now represents the Afghan government's refugee ministry at the camp. 

"There have been crackdowns every three, four years, but this time has been the worst."

- 'Overwhelming' fear -

An estimated 600,000 Afghans have arrived since the Taliban seized power in Kabul in August 2021 and imposed their austere version of sharia or Islamic law.

Lawyers have said the police operation has been complicated by registration cards for vast numbers of documented Afghans expiring at the end of June, although their status remains in place until the government rules on their renewal.

Naqibullah, who lives in a rudimentary house in the camp, said he and his father handed over 46,000 rupees ($160) to avoid jail after they were picked up by police, despite being documented refugees with permission to legally remain in Pakistan.

They were advised to keep a low profile to avoid re-arrest and stay away from the kiosk they run outside the camp. 

"Leaving our business behind is never an easy decision but the fear is so overwhelming that I can't even venture out to the market. We have no choice but to remain at home," he said. 

Pakistani lawyer Moniza Kakar said she can do little for Afghans who do not have documents, and that those recently deported include the sick and poor, as well as human rights defenders and women students.

More than 1,800 Afghans were deported from Karachi last year, city police said, and nearly 1,700 have been arrested so far in 2023.

But Kakar, along with the several other lawyers giving free legal help to Afghans, said the vast majority in this sweep are documented, compared to roughly a quarter rounded up in past crackdowns.

"Our action is purely aimed at illegal immigrants," Karachi police chief Khadim Rind told AFP, adding that allegations of arrests of legal document holders and bribe-taking should be investigated.

- 'Obeying the law' -

Afghan consul general Syed Abdul Jabbar said Afghans in Pakistan were paying the price for disputes between Kabul and Islamabad.

Relations have soured since the Taliban government seized power, with a sharp rise in militant attacks along Pakistan's border that Islamabad alleges are being planned on Afghan soil -- a charge Kabul denies.

A long-running border dispute has also seen key trade crossings closed for days.

But these issues should be "sorted out at the negotiating table", Jabber said. "A crackdown on Afghans is the wrong approach."

The pressure has seen some families sell what they can and return to Afghanistan, refugee community leaders said. Others were reluctant to uproot their lives to return to a country mired in its own economic crisis, despite the end of decades of fighting.

Day labourer Habib has been a refugee in Pakistan for more than half his life but says he lost his documentation several years ago. 

"I have lived with more freedom here than in our own country," the 76-year-old told AFP.

"We don't have documents and we are afraid they will give us trouble, but we are obeying the law," he said. "If they don't forcefully kick us out, we won't go to Afghanistan."

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