A whistle shrills, and a dozen boys tear across a gray schoolyard. Some are in sneakers, others have bare feet slapping the concrete. "This is a physical education class," announces Metin Yildiz, the director of education at Elbeyli refugee camp in southern Turkey.

About 24,000 Syrians have been living in this government-run camp for three years, costing the Turkish government $3 million a month, and our guides are keen to show us Turkish classes, a kindergarten, a computer lab, an art display.

But among the refugees, all the talk is of the people still in Syria, trying and failing to get to where we are. In a salon where women are training to be beauticians, Nour Mohammad stops practicing a blow-dry on a little girl to tell us about her loved ones who are on the run, north of the city of Aleppo.

"The most important thing is that my brothers and my relatives are all there," says the 21-year-old, who wears a bright headscarf and immaculate makeup.

Even as international leaders worked to wrangle a ceasefire, northern Syria has been wracked by intense fighting in recent weeks, and Russian air support for Syrian President Bashar Assad has ratcheted up. Tens of thousands of people have fled.

The truce took effect Saturday, but there is widespread skepticism and it was not immediately clear how widely it would be observed.

Since the Syrian war erupted five years ago, Syrians have been able to escape to Turkey. But the once-porous border has in recent weeks been much more tightly controlled, and tens of thousands of civilians are trapped on the Syrian side.

The clinic in this camp is a little overcrowded, but the Syrians do have access to treatment. On the Syrian side of the border, hospitals have been hit by airstrikes. Aid routes have been blocked.

A woman named Sultan, too afraid to give her last name, says her opposition-held village was besieged and then taken over by Syrian government loyalists.

"I also have relatives in the countryside north of Aleppo," she says. "Of course they want to come here but they can't." They went to the border crossing of Bab al-Salama but were stopped by Turkish authorities.

"The situation is terrible there," she adds. Camps on the Syrian side of the border have swelled. They are short of toilets and tents, and there has been heavy rain.

In the nearby Turkish town of Kilis, a Syrian aid worker named Asaad Ahmed, tells me he was over the border with the newly-displaced last week. "Most of the tents have no base whatever, so when there is rain or wind they will all be washed out," he says.

In the Syrian border town of Azaz, he says there are almost 50,000 families not even receiving bread, let alone other humanitarian aid. Hundreds of thousands of people in northern Syria rely on aid to keep going, but recent fighting and movements of large numbers of people has left humanitarians overwhelmed.

Like some international rights organizations and governments, Ahmed thinks Turkey should let vulnerable civilians over the border.

But Turkey has already taken in 2.6 million Syrian refugees, more than half of the 4.7 million Syrian refugees overall, according to the United Nations High Commissioner for Refugees.

The governor of Kilis, Suleyman Tapsiz, points out Turkey has also been under pressure from the United States and others to tighten the border, and stop jihadists getting into Syria.

"'Please protect your borders,' the USA said to us," he says in an interview at his office. "And right now, right now we are protecting our borders very strictly."

The governor says people with the right paperwork, and the wounded, are still allowed to cross. And, he says, Turkey should be allowed to use tough measures. The U.S. does. He even visited the U.S.-Mexican border and shows me his report about the border controls there.

"When the Turkish police established a checkpoint on the highways, people were criticizing Turkey," he says. "But as you see this is the an American checkpoint on the highway." He shows a picture of a canine search of a vehicle.

Tough measures don't stop people trying to get in, but they do raise the price. I meet one Syrian refugee, Rana Hammoud, who tells me some relatives managed to get to Turkey earlier this month.

It cost the impoverished family $1,300 for each member who crossed, she says.

"People are selling the land back home," she says as she waits for a food handout from a Turkish charity. "And then they go."

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