PISKY, Ukraine — Since a cease-fire was declared in eastern Ukraine on Sept. 5, nearly 1,000 soldiers and civilians have died in a grinding conflict with rebel separatists that is being waged largely out of sight. That is almost a quarter of the 4,317 killed since April and an average of 13 a day, the United Nations estimates.

Over the same three-month period, the Ukrainian military says it has recorded 3,412 rebel cease-fire violations, while separatist fighters regularly accuse Ukrainian forces of shelling the region’s biggest city, Donetsk, killing civilians. And Russia has continued to build up the rebel forces, sending in troops, military vehicles and heavy weapons, including what Ukraine says was a convoy of 85 vehicles this week carrying heavy armor, fighters and ammunition.

All this has made for a nervous few months for the Ukrainian soldiers in the village of Pisky, who endure almost constant shelling, sniper fire and raiding parties from the rebel separatists only a mile away on the front lines of a confrontation that carries the potential, at almost any moment, of exploding into a hot new theater in a revived Cold War.

The front zigzags through a glum tableau of abandoned houses, muddy fields and trash-strewn streets, where all but a few retired people have long since fled. The two sides are only about a mile apart, so close that they can see each other’s positions through a high-powered periscope.