A group of migrants huddles beside a small, smoky fire inside an abandoned building in northern Serbia, the last moments of warmth before they set out into the driving snow toward the razor wire, cameras and sensors of Hungary s electrified border fence.
A few hours later, they return, their efforts to cross through Hungary and toward Western Europe thwarted by the three-meter (10-foot) fence and heavy Hungarian police patrols which, after intercepting them, escorted them back across the border into Serbia.
