Following the Western-backed uprising in Ukraine that installed an EU-oriented administration in Kiev, the Ukrainian government has seen significant opposition to its rule in the eastern and southern parts of the country. Pro-Russian and anti-government demonstrations have intensified across eastern and southern Ukraine in cities such as Donetsk, Kharkiv and Odessa. Starting in early April, armed groups in Ukraine's eastern reaches stormed regional administration and security buildings, following a pattern similar to that seen in Crimea. Such groups still control more than a dozen buildings in the Donetsk and Luhansk regions. While it is difficult to specify the exact size of pro-Russian militant groups in the east, it is likely that no more than a couple of hundred well-armed men currently are occupying buildings and manning checkpoints throughout eastern Ukraine. These armed groups are concentrated in the two easternmost provinces of Luhansk and Donetsk, where pro-Russian sentiment is highest in Ukraine. Within Donetsk, the largest and most professional armed groups are in Slovyansk; a key gateway city on the road from Donetsk to Kharkiv, the municipality is now regarded as a stronghold for separatist militants.
There have been no indications that these armed groups have grown substantially in size since the initial storming of the buildings on April 6. However, these groups are supported by larger bodies of unarmed protesters, numbering in the hundreds or low thousands. For the most part, Ukrainian security forces' anti-terrorism operations have not supplanted the armed separatist groups from the buildings and areas they have seized. Security forces have been able to dismantle some checkpoints and wrested control of an airfield in Kramatorsk from separatists but have not been able to penetrate farther into the city of Slovyansk. The Ukrainian military has sought to avoid civilian casualties out of fear of inciting anti-government and pro-Russian sentiment. Instead, Ukrainian forces have attempted to blockade the separatists within Slovyansk in an effort to constrict the group's supplies and potential reinforcements. A standoff has ensued between the separatists and Ukrainian security forces in the region, though the potential for further clashes and building seizures elsewhere in eastern and southern Ukraine remains during the upcoming May Day holidays, May 9-11 — a high point of Soviet nostalgia in the region. Despite the relatively small size of the pro-Russian armed groups in the east, Ukraine is not in a position to impose its will. The degree to which Kiev and its Western backers are willing to compromise on key political issues with Moscow will determine how aggressive Russia will be in its military posturing and future support of armed groups in eastern Ukraine.
