Tajigul Haidary had overstayed her residents' visa in Iran and was expecting just a hefty fine when she went to renew it, she said. Instead, she was arrested as an illegal immigrant, imprisoned, held in a transit center with hundreds of other Afghans and, early this week, deported at a dusty border point back to Afghanistan.

It's a homeland that she hardly knows. Her family took her to Iran when she was nine years old. Now 26 years old, she is married to another Afghan in Iran, has a 4-year-old son and an 8-year-old daughter and is five months pregnant. When she was deported, she was wrested away from them.

"My husband tried his best to get me out but they wouldn't listen to him. My children cried, but it made no difference. I don't know what to do. I have to get back," she said, tugging at the voluminous black chador warn by many Iranian women, as she sat on a plastic chair in a shed at the Islam Qala border crossing.

Around 25,000 Afghans a month are deported from Iran at Islam Qala — nicknamed "Zero Point" — along with another 30,000 a month who cross returning home voluntarily — a sign of Tehran's efforts to control the huge numbers of Afghans who flock to their neighbor. Iran has long been an outlet for Afghans, either searching for work to escape poverty or seeking refuge from their country's chronic wars and instability.

Many Afghans are concerned that Iran is looking to shut off that outlet by clamping down even more on illegal migrants.

During a visit by Afghan President Ashraf Ghani to Tehran on Sunday, Iranian President Hassan Rouhani told him that the issue of Afghans in Iran "must be settled." Rouhani said Afghans living in Iran would be registered "so that the government can make appropriate decisions about them."

"Individuals who want to carry out business activities or study need to do so under legal requirements of obtaining visas," Rouhani told journalists after the talks.

Millions fled from Afghanistan to its neighbors Iran and Pakistan during the 1979-1989 Soviet occupation of Afghanistan or after the Taliban came to power in 1996 — creating one of the world's largest and longest refugee situations. Both Iran and Pakistan have been pressing for them to leave, and in the past 12 years, the U.N. refugee agency UNHCR has helped repatriate some 5.8 million Afghans who voluntarily agreed to return home.

But the number of willing returnees is dwindling. At the same time, Afghans slip constantly into Iran looking for work in their better-off neighbor. Throughout Iran, Afghans fill menial jobs like construction and some have lived in the country for years. As a result, there are not only around 950,000 registered Afghan refugees in Iran with legal status but 1 million to 1.4 million undocumented Afghans, according to estimates by the International Organization for Migration. In Pakistan, there are some 1.6 million registered Afghan refugees and an estimated 1.5 million undocumented ones.

Iran appears to be taking whatever chance it can to deport Afghans without documented status or unregistered as refugees with the UNHCR.

IOM's communications director in Afghanistan, Matthew Graydon, said up to 10 percent of the returnees from Iran are vulnerable minors, girls and boys between 13 and 17 years old who could fall prey to traffickers, as well as mentally and physically disabled people, women traveling alone or single mothers. But neither IOM nor the Afghan authorities can offer help to all those who need it.

He said there has to be a concerted effort from humanitarian agencies and the Afghan, Iranian and Pakistani governments to find a long-term solution to their situation "so people won't get caught in the cycle of deportation, exploitation and issues such as that."

Traffic at Zero Point, 115 kilometers (71.5 miles) west of the provincial capital of Herat, is mostly one way — people coming out of Iran, willingly or not, along with trucks loaded with concrete, steel and fuel being imported. The trucks mostly return to Iran empty since Afghanistan, one of the world's poorest countries, offers little to export besides its desperate people.

"At 2 o'clock every afternoon, about 30 buses arrive carrying about 500 returnees. We do a random sampling, checking that they are who they say they are, and record their biometric details," Maj. Abdul Rafah Watander, head of the Afghan border police at Islam Qala, told The Associated Press. Among those being deported are sometimes Afghans who had legitimate visas in Iran but were arrested and expelled for no apparent reason, he said.

The border guards try to sift out criminals or people with special needs who need care among the crowds, but with limited staff they can only check about 100 people a day, while the others just go through, Watander said.

The actual border at Zero Point is marked by two shacks on each side along the strip of asphalt — Iranian guards in desert-camo fatigues, Afghans in green fatigues. The border stations on each side show the vast difference between the two. On the Afghan side are rickety shacks with broken windows and containers converted to offices on the Afghan side. On the Iranian side, wide roads, cellphone towers, mounted CCTV cameras, and a long snaking line of trucks.

As 2 p.m. approaches, buses, cars and vans start to cross. Once on the Afghan side, hundreds disembark and trudge to be screened, categorized and, if they need it, helped. Boys with wheelbarrows tout for business carrying luggage. One recent afternoon, two vans arrived with wooden coffins strapped to the roofs, repatriating dead Afghans for burial.

The vast majority of the arrivals are young men caught in Iran after paying traffickers to sneak them in for work.

One, a 16-year-old named Nurullah, said he was among 26 young men from his village in Faryab province, north of Herat, who paid $200 each to traffickers to take them to Iran's capital, Tehran. The traffickers took them along a long route across the southern part of the border, and they made it as far as the Iranian city of Isfahan, 340 kilometers (210 miles) south of Tehran. There, police caught them.

Nurullah, who like many Afghans goes by one name, said there's hardly any young men left in his village since they all leave to find work elsewhere. His older brother worked for two years in Iran and earned decent money before coming home.

Some young men try repeatedly to get work in Iran. But Nurullah said he won't be slipping back across the border. "It was just too stressful. I'll stay at home from now on and find whatever work I can. And maybe a wife."

____

Associated Press writer Ali Akbar Dareini contributed to this story from Tehran

Follow Lynne O'Donnell on Twitter at https://twitter.com/lynnekodonnell