Valery Bolotov was wounded in an assassination attempt on 13 May. Luhansk People's Republic authorities blamed the incident on the Ukrainian government. Government forces later captured Alexei Rilke, the commander of the Army of the South-East. The next day, Ukrainian border guards arrested Valery Bolotov. Just over two hours later, after unsuccessfully attempting negotiations, 150 to 200 armed separatists attacked the Dovzhansky checkpoint where he had been held. The ensuing firefight led Ukrainian government forces to free Bolotov.