YUMURTALIK, TURKEY — Going against the flow of recent days, Zaim Mahmoud drags his three children in the direction of bombings and clashes. For this family, one of tens of thousands to flee an Islamic State offensive against Kurdish areas in Syria, help did not come fast enough.

The lines of sorrow run deep on his sun-beaten face. Mr. Mahmoud, who is 70, became a widow less than a fortnight ago. His sons Mohammed, Mahmoud, and Hazim, shuffle next to him, their gaze pinned on the pavement, still coming to terms with a childhood cut short by war and loss.

“I have nowhere to go, no one to help, and no money to feed my children. Our fate is in God’s hands now,” he says, still mourning his wife, who died of natural causes. He cannot go back to his hamlet of Khosli Wastani because it is under IS control, he says, so he will go to the besieged Kurdish border town of Kobane instead.

Beyond his field of vision, just a few miles away, large white tents rise up against a fleeting dust storm. Still empty, the nascent refugee camp comes in response to the worst humanitarian crisis that Turkey has faced since the start of the conflict in Syria more than three years ago.

“This number of people in such a short period of time is the highest we have seen” in Turkey, says Selin Unal, spokeswoman for the United Nations High Commissioner on Refugees, in an interview held next to one of two open crossing points.

Turkey’s uneven burden

More than 140,000 people fled Syria in the past few days. In a poignant reminder of the uneven burden Turkey shoulders as a result of the war next door, that number matches Europe’s total refugee intake since April 2011. Before this influx, Turkey already counted 1.5 million refugees, a tally that includes unregistered individuals.

The Turkish government, assisted by international and local aid agencies, is racing against the clock to provide for this rapidly swelling population. Its border policy is a delicate balancing act. On the one hand, the lives of many depend on ease of entry. On the other, the government is under huge pressure to tighten its border to stymie IS.

Those dueling needs are rapidly transforming the landscape around the border town of Suruc, a short walk from Kobane. Earth mounds to conceal tanks rise along the border as temporary shelters are built. Convoys of military vehicles skirt the perimeter, raising clouds of dust that blanket dazed refugees.

Not every one in need gets through. Some have been turned back. Scores of Turkish Kurds have headed to Suruc, most with the intent of providing help to refugees, some wanting to cross into Syria to fight, and others hoping to pressure the authorities to do more.

The result is asymmetric clashes with riot police, new checkpoints, and patrols.

Horror stories in the dark

While Kurdish communities in Turkey have absorbed a solid portion of the new arrivals, hundreds are still sleeping under the stars in open fields. Sitting at night under a cluster of olive groves, shepherds listen to the jarring concerto of bombs and gunfire played out in the tiny hamlets they once called home.

They share their horror stories in the dark, their voices hoarse from thirst. “In every Kurdish area that they take, Daash [IS] starts beheading people. We have seen countless bodies, severed heads propped on the bellies,” says Botan, a native of the village of Zobava. He says IS fighters killed two of his relatives in battle and detained a third.

At the light of dawn, new arrivals report the same. “We’ve spent seven days running from hamlet to hamlet as Daash slaughters everything in their path. Sometimes they come in and kill men in their sleep. They are plundering and burning our homes, selling as sex slaves any woman they capture,” says Azzan Abdi.

Mr. Abdi crossed the border on Wednesday along with three wives and 25 children.

Without access to Syria, such anecdotes are impossible to verify, but dozens of individuals interviewed by The Christian Science Monitor expressed similar fears and accounts. A volunteer with the Syrian Red Crescent shared images purportedly showing Syrian Kurds who were beheaded by the Islamic State in recent days.

For families who have been split up by events, the uncertainty is too much to bear.

Mustafa Ramadan spent five days sleeping on the border before being allowed into Turkey. Now he wants to turn back to fetch his elderly mother who is one of hundreds still waiting to be allowed in at an informal crossing. She is trying to get the green light to enter with all they have left: three sheep.

Many crowd along the border exchanging calls with relatives on the other side. Those who cross are now registered and provided with basic health care on arrival. They sit in a pen framed by police, uncertain of their fate. Those waiting to get in, just a few yards away, stand ready to bolt and brave mines at the first whiff of IS.

“If they don’t cross in the next hours, they will die of thirst and hunger,” warns Sadiq Malla who has been waiting for his brother and relatives for days

This post originally appeared in The Christian Science Monitor