A group of men wearing white camouflage against a blanket of fresh snow run drills to hit back against Russian saboteurs who might infiltrate behind Ukrainian lines.
The front line in Ukraine has barely shifted in more than a year of fierce fighting between Kyiv and Moscow, but both sides say they have conducted operations against threats behind their own lines.
A dozen men jumped from an aging Soviet-era T-64 tank and fired off blank rounds as they advanced towards a trench they needed to capture as part of the exercise.
Others assuming the role of Russian forces were hunkered down to fend off the assault held at a vast camp on the edge of a pine forest in the biting cold.
“The Sumy and Chernihiv regions are faced with the threat of sabotage groups coming from the territory of the Russian Federation,” Serhiy Nayev, Commander of the Joint Forces of Ukraine told AFP.
The territories on Ukraine's borders with Russia and Moscow's ally Belarus have remained tense, even after Kyiv's forces beat back invading troops in both regions last year.
“Last week there were three attempts by sabotage groups to penetrate our defenses,” Nayev said.
Yevgen Sylkin, a military spokesman responsible for Chernigiv, said Ukrainian forces respond to around 10 attempted Russian incursions a month from groups made up of around 10 or so people.
Their aim, he said, is to destroy military facilities and stir panic among the civilian population.
“We are pushing them back,” Sylkin added.
The anti-sabotage exercises included drills on using basic firearms, attacking trenches, evacuating wounded servicemen and flying drones.
“Some guys come and don't know what an assault is. They're only ready for defense. During the assault, the newcomers are scared, but there is nothing to worry about,” said Oleksandr, an instructor who declined to give his last name citing security concerns.
“We give them the basic skills and then they build on them,” he added.
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