May 16, 2014 the Ukrainian government started an anti-terrorist operation against pro-Russian insurgents in the Donetsk Oblast in early April 2014. Pro-Russian protesters and insurgents affiliated with the DPR

captured and occupied numerous government buildings, towns, and territories in the region. In Donetsk

city itself, many government buildings were under separatist control. During the morning of May 26, pro-Russian insurgents captured the terminal buildings of Donetsk International Airport, and demanded the withdrawal of government forces from the area. Soon after, Ukraine issued an ultimatum to the insurgents, demanding they surrender immediately. This was rejected, causing paratroopers to launch an assault on the airport, accompanied by airstrikes against insurgent positions.