in the campaign “Continuation of the Russo-Ukrainian War: Armed Aggression in the Donbas (2014–2015)”
The overt crossing of the state border by regular Russian troops in the summer and autumn of 2014 to save the separatists from defeat: the "DNR" commander admitted that the decisive role was played by Russian servicemen who came "on leave" - "it was mostly 'vacationers' who advanced on Mariupol. When they left, both the front line and the opportunities became precarious"[1]. The offensive resulted in heavy losses for the Ukrainian army near Ilovaisk and Debaltseve. The presence of regular troops continued into 2015: the GRU men captured near Shchastia were "soldiers of the 3rd Separate Guards Special Purpose Brigade of the Main Directorate of the General Staff of the Russian Armed Forces, who arrived on the territory of Ukraine on March 26 and were quartered in Luhansk"[2].