Russia has deployed a significant number of air defense systems to eastern Ukraine, reports from local sources and the Ukrainian security services say. Medium-ranged Buk M1-M2 air defense systems cover most of the separatist-held areas, and shorter-ranged systems such as the Pantsir-S1, Osa and Tor cluster around the strategic supply lines running from the Russian border into the main cities of Luhansk and Donetsk. The systems combine to create a layered air defense infrastructure that prevents the Ukrainian air force from using its assets over separatist-held areas. Even though a Sept. 5 cease-fire agreement explicitly rules out Ukrainian air operations over separatist-held areas, and the Ukrainian military has not attempted any such operations since then, the Russian move to establish this air defense presence indicates strong commitment to defending the separatist-held territory.
The deployment of these air defense systems, as well as measures by artillery units to prevent the Ukrainian military from massing forces for an attack on separatist-held areas, seem to serve a mostly defensive objective. However, separatist units continue to fight to expand their territorial hold over smaller areas along certain positions on the front line. They have continued to encircle and then take over Ukrainian checkpoints in areas near Luhansk, while bitter fighting between both sides continues at the Donetsk airport. The Ukrainian military's positions at Debaltseve, a strategic town that controls the main highway directly connecting Donetsk and Luhansk, have also been contested. As the separatist and Russian forces seek to consolidate their positions there, they may still make significant attempts to seize this location.
Even though the cease-fire has not been completely implemented and skirmishes continue to break out along the front line, the shape and posture of Russian reinforcements do not necessarily indicate a further escalation of the conflict between Ukrainian forces and separatists. Instead, Russia seems to be consolidating the gains made prior to the cease-fire declaration, securing the separatists' hold on the territory they currently control. There are no indications of an expanded campaign further into Ukraine.
