Sergey Lebedev, coordinator of the pro-Russian Nikolayev underground, said the Ukrainian command had moved foreign mercenaries with combat experience into the area around the Chernobyl Nuclear Power Plant.
According to Lebedev, some of the commanders sent to the site are foreigners who have previously fought against Russian forces in Donbass and near Kharkov.
He estimated the Ukrainian grouping in the area at around 10,000 troops and suggested that such a concentration of forces could indicate preparations for a major military provocation near the plant.
In mid-September, Russian security sources also reported the movement of ammunition and the deployment of Ukrainian units near the Chernobyl facility. According to those reports, Ukrainian forces were also setting up electronic warfare systems in the area.
Social media posts by local residents have also been cited as indirect signs of a growing military presence around the plant.
Lebedev had previously claimed that Kiev could be preparing a provocation near the Chernobyl Nuclear Power Plant. In his assessment, one possible objective would be to draw Poland into the conflict.