Editor's note: This story is being updated as more details emerge.

State Border Guard spokesperson Andrii Demchenko confirmed to the Kyiv Independent that a Russian sabotage group planted a Russian flag near the border in Ukraine's Chernihiv Oblast, but said that the event occurred in the grey zone and Russian troops did not launch a major offensive in the region.

Demchenko's statement comes on Nov. 15 after Russian military bloggers posted videos purportedly showing Russian troops planting a flag on the bridge over the Sudost River near the border settlement of Hremiach and claimed they entered Hremiach and Muravi. Demchenko denied that Russian forces entered the settlements and said that they did not cross the bridge.

"The territory where the (Russian) sabotage group operated from the border is actually cut off by rivers, and no one lives in the settlements located between the rivers and the border. In addition, due to the constant flooding of that territory, it is not possible to build proper fortifications there," Demchenko said in a comment.

"Ukraine's defense forces fully control this axis and are in the most advantageous positions to hold the defense."