JARABLUS, Syria—The convoys arrive day after day, a motley cavalcade of old pickup trucks, motorbikes with sidecars, and cobbled-together three-wheel farm vehicles packed with destitute Syrians who are fleeing the U.S.-led offensive to oust the so-called Islamic State from its capital, Raqqa, and the region around it.

At least 10,000 internally displaced Arabs have arrived here in the past month alone, according to local officials in this Turkish-controlled zone of northern Syria.

They’re only a sliver of the 200,000 civilians the United Nations says have been made homeless by the U.S.-backed offensive since November—160,000 in the last two months alone. Some have returned to their home villages. But a vast number are living in the open, in tents, in their cars, or in makeshift camps.

The U.S. government isn’t taking responsibility for displaced civilians, having handed over that responsibility to its chosen partners on the ground, led by a controversial Kurdish militia.

Interviews with four internally displaced families reveal a pattern of discrimination that is sure to sow enmity for years to come between the Arab majority and the Kurdish minority in northern Syria.

After U.S. bombing ousts ISIS militants from the villages they’ve occupied, the proxies on the ground set up by the U.S.—the Syrian Democratic Forces—enter the villages and order the mostly Arab population to leave at gunpoint. People say they are stripped of their identity cards and herded like livestock to a transit camp.

The SDF, which has Arabs in its ranks but is dominated by Kurds, tells these internally displaced persons, or IDPs, as they are called in humanitarian jargon, that they can return to their homes if they find a local sponsor. Otherwise, their only option is to exit the region. Many arrive in Jarablus bearing only travel papers authorizing a one-way trip out of the Raqqa area within 24 hours.

While this sounds like a Kurdish-led “ethnic cleansing,” the State Department says tens of thousands of Arabs returned to their homes in the early stages of the operation. But the SDF’s current practice of requiring a sponsor and seizing IDP identity papers appears to be a breach of International Humanitarian Law, officials say.

Jarablus is a border town captured in the Turkish-backed Operation Euphrates Shield last August. It’s a magnet for IDPs from all of northern Syria because it’s safe from bombing by the Assad regime and Russia, thanks to Turkey’s military presence. Some 5,000 IDPs from Raqqa are living in Jarablus alone, and another 5,000 are scattered across the 810 square miles Turkey controls, many living in tents set up by the side of the road, local officials said.

“They [the SDF] told us, ‘You can go anywhere you want, but not to our areas,’” said Khiro Abdullah Aboud, 34, who arrived in the Turkish-controlled zone with his wife and five children early in May.

Abu Yasser, 60, a fisherman and permanent resident of a village near the Tabqa dam, had a similar story. He and his family of 12 fled a U.S.-led attack on foot and arrived here last week after a harrowing six-day journey by bus and pickup truck. “They told us, ‘Arabs cannot stay here,’” he said.

Fifty miles southwest of Jarablus, Mohamad al Omar , 74, pitched a tent for his family of 14 after they were forced out of a village near Raqqa following U.S. bombing.

“The Kurds expelled me, my family, and the entire village,” said Omar, interviewed in Dabiq where he arrived in a beat-up pickup truck two weeks ago. “They called us filthy names—asses, animals.” One Kurdish fighter called him a “traitor working for Turkey and against us.”

At the camp in Ayn Issa, north of Raqqa, where people fleeing undergo security checks, those in charge say IDPs in fact have another choice, to stay there indefinitely. But that means living in a tent with limited access to water, almost no food, and practically no services. Of the 150,000 people Ayn Issa has processed since November, some 8,000 have chosen to remain, volunteers say.

The U.S. government, which is leading the assault on Raqqa, appears to be detached from the humanitarian consequences of its military operations.

Take the Ayn Issa camp. “The Americans are present. They have visited the camp. They only take pictures and leave,” said Omar Alloush, spokesman for the Kurdish Democratic Union Party or PYD, which runs northern Syria.

The State Department said in response to questions from The Daily Beast it had seen “reports” of displacements. “We are concerned by any claims the populations have not been permitted to return,” a spokesman said. “We continue to engage SDF leadership and local authorities to permit the safe, voluntary return of all IDPs to their homes.”

But the Department declined to answer questions about the treatment of IDPs en route, the seizing of their documents, the issuance of restrictive travel papers, the SDF’s sponsorship requirement or the operation of the Ayn Issa camp.

On Wednesday night, the Department for the first time indicated there is a crisis. In a new statement, it said it’s “working with our partners on the ground to scale up the ongoing humanitarian assistance to civilians in urgent need of food, safe drinking water, and urgent medical care.”

The U.S. Central Command claims to know even less about forced displacements. “We have not heard any substantiated reports of these events,” it said when asked about the complaints of newly arrived IDPs.

“Coalition support to our Syrian partner forces is focused on providing intelligence, surveillance and reconnaissance; advisers, precision air and artillery strikes and equipment and training,” CENTCOM said in its emailed message.

The Command said, “International Humanitarian Assistance organizations located at different camps throughout northern Syria, but we cannot speak to their specific roles at each of the sites.” But it is apparent on the ground that they’re not there at all.

The Command declined to comment on the SDF practice of requiring IDPs to find a sponsor in order to return to their villages, but said the Coalition “supports the right of residents throughout northern Syria to govern themselves and to prevent a return of ISIS.”

The UN is a lot more blunt . “Freedom of movement of internally displaced persons remains a concern with regards to the ongoing displacement in Raqqa [area], due to the security screening and sponsorship requirement imposed by the People’s Protection Units-led Syrian Democratic Forces for those displaced to remain in the area,” said a May 23 report by the UN secretary-general (PDF).

According to a May 28 UN report, 200,000 civilians have been made homeless since November (PDF)—all from ISIS-controlled towns and villages surrounding Raqqa. The UN Office for the Coordination of Humanitarian Affairs said 20,000 arrived in the camp last week alone—more than 9,000 over two days. At one point, Kurdish authorities had reportedly decided to prevent IDPs from leaving the camp, but the camp management chose not to enforce the rule, the report said.

The apparent lack of alarm in the U.S. government about the human distress stemming from the Raqqa offensive seems out of keeping with the longtime practice of fielding civil affairs teams into areas of U.S. military intervention. But that’s by choice.

In fighting ISIS, “we work by, with and through our partner forces, Iraqis and Syrians,” said Col. Ryan Dillon, spokesman for the U.S.-led coalition. “They are leading the patrols, conducting the raids, standing up governments and picking their projects,” he said in an email.

The neglect is evident at Ayn Issa camp itself, which now has UN tents—700 serving 1,000 families—but little else. The UN secretary-general’s May report said 35,000 people were in Ayn Issa and the surrounding area in April, but the majority were living in the open.

The UN said it had provided food for 8,230 people at Ayn Issa in the week of May 15-22, when 20,000 had arrived.

“We get very little aid from anywhere,” said spokesman Alloush of the PYD. Ramadan began Saturday, a month-long period of daytime fasting for Muslims, which is broken at sundown each day by an Iftar, a special dinner. But at Ayn Issa, Alloush said he could muster Iftar food for only 100 families Saturday, and the others had to fend for themselves.

Abdulsalam Hamsork of the Raqqa City Council, a government in exile appointed by the SDF, predicted a “catastrophic situation” when the main military operation begins to clear ISIS from the city of Raqqa, expected in the next month.

Reporting on the civilians displaced by the Raqqa offensive has been sparse, partly because of limited access. Citing security concerns, the Turkish government restricts reporters’ access to the territory that it controls. The government permitted a Daily Beast reporter to travel here only under escort and provided an armored SUV and armed Syrian rebel units in two pickup trucks for protection.

Kurdish-controlled northern Syria, a 130-mile strip of land on the Turkish border which the PYD calls “Rojava” or western Kurdistan, is a different story. The PYD’s military wing, the People’s Protection Force or YPG, is the Syrian affiliate of the Kurdistan Workers’ Party or PKK, which is at war with Turkey, and Turkey has closed all border crossings into that region. The PYD has often collaborated with the Assad regime, which installed it in power in this part of Syria, and no government in the region recognizes its legitimacy. Reporters can gain access only through northern Iraq if the border with the Kurdistan Regional Government is open.

Moreover, Turkey vehemently opposes the U.S. reliance on the YPG militia as its proxy ground force, and the decision by the Obama administrations and now by President Donald Trump to proceed with this local alliance has soured relations between the two NATO allies.

Although Turkey has been a principal aid conduit for IDPs elsewhere in northern Syria, it doesn’t allow aid shipments across the border in the Kurdish-ruled zone, forcing the UN to fly supplies to the Syrian government airport in Qamishli then truck them to Ayn Issa, a five hour trip. This creates a nearly impossible situation for local administrations trying to distribute humanitarian aid.

Caught in the standoff between NATO allies is the mainly Arab population displaced by the U.S.-led war on ISIS. Many are IDPs several times over, having fled the fighting elsewhere in northern Syria.

Al Omar and his 14-member family are from Deir Hafer, east of Aleppo, where he worked as a farmer. They fled to ISIS-controlled Maysaloun, a village west of Raqqa, early in February. There he tried to smuggle his family into the Kurdish area. But ISIS militants stopped him, shooting at his 1974 pickup truck, and he had to go back to the ISIS area. Then the U.S.-led coalition bombed ISIS in Maysaloun and the Kurds took the village.

“I couldn’t go to the Kurds,” he said. “They came to us.”

The SDF ordered the residents of Maysaloun and other nearby villages—more than 500 people—to go to Ayn Issa about 20 miles away, confiscating their identity cards en route. Many others departed in frustration without their identity cards, but Omar stayed at the camp for seven days, until he got his back.

“In that time, I got two packets of bread,” he said. But the family came through in good fettle, partly because shelter was not a problem. “I’m a Bedouin. Bedouins carry their own tents,” he said.

Abu Yasser, 60, a fisherman from Al Dibsi , west of Tabqa, which the SDF captured in early May, didn’t have transportation nor his own tent. He and his family of 12 fled attacks by the Assad regime from the south of their village and the SDF from the north. “We came on foot,” he told The Daily Beast in Jarablus, where he arrived in the middle of last week. The Kurdish-led forces moved the family out of the region in stages. They slept in mosques overnight, and when a big enough group formed, would be moved to the next town.

“When we left our village, we didn’t have any destination in mind,” said the fisherman. “We wanted to go to any place that would host us.”

Passing through Manbij, previously the biggest Arab city on their journey, the family asked to stop in a camp there.

“They said Arabs are not allowed to stay in Manbij,” he said.

Khiro Abdulla Aboud, 34, arrived in Jarablus on a three-wheel farm vehicle in early May with his wife and five children. It was their fourth stop in a four-year journey that began in As Safira , southeast of Aleppo. When the regime captured it from rebel forces about four years ago, they moved to Maskana , an ISIS-controlled village outside Manbij about 60 miles to the northeast. The regime attacked Maskana in mid-March, and they moved again, this time to Hazima about 40 miles southeast, a village northeast of Raqqa.

Late in April, the SDF captured nine villages in the area and ordered all the inhabitants to leave at gunpoint.

“We were herded like sheep,” Aboud said. “They called us Arabo -Daesh,” using a pejorative Arabic term for ISIS. They were on the move for 10 days, camping in the open, until they reached a transit camp in the village of Khneiz where they were told to bring a sponsor so they could return to their village.

“I didn’t see anyone bringing a sponsor,” he said.

The armed guards then asked for each of the villages to provide the names of 50 men who could return to the village to protect it. Aboud later got word that the volunteers were taken directly to the front line. In one village, 25 men volunteered—but only 10 came back alive, he said.

From Khneiz, they were then ordered to Ayn Issa for final processing. There, the authorities wrote up a paper authorizing him, his family, and about 50 others to exit the Kurdish-controlled region. “It was a deportation,” he said.

Aboud and his family now live in and under the three-wheeler.

—with additional reporting by Duygu Guvenc in Ankara