TORKHAM: Crossing back into his native Afghanistan from Pakistan, Nezamuddin wept as he recounted the hardships his family of 11 had faced in their years as refugees, troubles that only grew insufferable after a recent terror attack there killed 150 people.

“Whenever there was a bomb blast they would arrest us for it, beat us up, take our money,” said Nezamuddin, who goes by one name like many Afghans.

“Now I don't know how I am going to look after my old father, myself and my mother."

Since January, almost 50,000 Afghans like Nezamuddin's family have passed through Torkham, double the amount of all refugees returning through the border town in 2014, according to the International Organization for Migration.

Many like Nezamuddin say they fled Pakistan over increased harassment by police who told them to return to Afghanistan, a country many have never even seen, putting new pressure on both countries to find solutions to the decades-old flow of refugees.

There are some 1.6 million registered Afghan refugees in Pakistan and up to an estimated 1.5 million unregistered Afghans live there, said Abdul Qadir Baloch, the Pakistani minister responsible for refugee issues.

Read| Pakistan world's largest host of refugees: UNHCR

Exact figures remain elusive as tens of thousands cross the border daily.

Pakistan initially welcomed waves of Afghan refugees after the 1979 invasion by the Soviet Union.

Also read: Not every Afghan living in Pakistan is a refugee, says UNHCR

But as years progressed, attitudes hardened. Many now see Afghan refugees as criminals or militants or responsible for taking jobs from Pakistanis.

Then came the Dec 16 Taliban attack on an army-run school in Peshawar, in which 150 people, most of them children, were killed.

Suddenly, Afghan refugees reported increased harassment by authorities checking their documents, demanding bribes and telling them they had to return to Afghanistan, Human Rights Watch said.

Also read| Stop forceful return of Afghan refugees from Pakistan: HRW

At Torkham, Afghan refugees now pour over the border with little more than the clothes on their backs.

Some arrive on foot, others in rented trucks with family members huddled between bags, boxes, mattresses and suitcases.

Awal Khan, a father of seven, spent 35 years in Pakistan, arriving as a baby when his parents fled after the 1979 invasion.

Also read: Govt agrees to review deadline for Afghan refugees’ return

Khan said he worked as a daily laborer, earning just enough to feed his family. Serious harassment began after the school attack, he said. “They went house to house, looking for Afghan refugees. They forced us to leave,” he told The Associated Press.

“I have no house to live in and no money to rent one. We will have to live in a tent."

Syed Liaqat Banori, who heads the Islamabad-based Society for Human Rights and Prisoners' Aid, said authorities often harass Afghan refugees following security incidents but this time was much worse.

“They are not asking them to leave the country but if they are harassed, they are asked to leave their houses, they are asked to leave the schools, colleges and close their businesses,” Banori said. “What they will do?"

Also read: Afghan refugee concerns

The Pakistani government denies systematic harassment targets Afghan refugees. “No harassment whatsoever is going to be cast on the unregistered Afghan refugees who are living here,” said Baloch, the government minister.

“We are going to take care of them."

Pakistani officials announced last week that they plan to register all unregistered Afghans in the country.

Pakistan and Afghanistan also have discussed new financial incentives to get more refugees to return home.

Sayed Hussain Alemi Balkhi, Afghanistan's minister for refugees and repatriation, told journalists on Saturday that the registration of Afghan refugees in Pakistan will begin with a month.

“The Afghan government wants all Afghan refugees to come back to their country, but returning all Afghans at once would create many problems,” he said.

But even the current flood of returnees is proving overwhelming for aid groups like the International Organization for Migration at Torkham, spokesman Matthew Graydon said. “The capacity here was designed for maybe 10 to 15 families a day and we are having much more than that,” he said.

“What we have here is a large gap in assistance that we are struggling to meet."