ISW: Russian forces building 30-km wall of freight cars in occupied Donetsk Oblast.

Russian forces in occupied Donetsk Oblast are assembling a barrier of train cars that stretches 30 kilometers long, the Institute for the Study of War (ISW) wrote in its Feb.

11 report, citing satellite imagery and Ukrainian Telegram channels. The barrier, nicknamed the "tsar train," may be intended to serve as another defensive line against advancing Ukrainian troops. Satellite images show the line of train cars stretching from Olenivka, south of the city of Donetsk, to Volnovakha, north of Mariupol.

The barrier is reportedly constructed from over 2,100 freight cars. The train barrier is about six kilometers from the current frontline at Novomykhailivka, the ISW said. Analysts said the line "is in an area of the front that was relatively inactive when Russian forces reportedly began construction," though Russian troops have made "marginal" advancements in the area more recently.

The barrier appears to be a new Russian defensive line, but the ISW said occupying forces could have "other purposes" in mind for the structure. Russia's lines of defense in the occupied regions have proved difficult to penetrate, stalling the Ukrainian military's counteroffensive operations on the eastern and southern fronts. Ukrainian troops are now also on the defensive in Donetsk Oblast, fighting off the Russian assault on the city of Avdiivka, whick lies kilometers away from occupied Donetsk.

The military reported Feb.

11 that Russia has been deploying more armored groups in its attempt to overwhelm the city.

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