This resulted in Donetsk People's Republic, where insurgents captured and occupied numerous government buildings, towns, and territories in the region.

During the morning of 26 May, pro-Russian fighters captured the terminal buildings of Donetsk International Airport, and demanded the withdrawal of government forces from the area.

[16] Sporadic gunfire was heard during the night, making it unclear if government soldiers were in full control of the airport.

[19] During the fighting, Druzhba Arena, home of the Kontinental Hockey League team HC Donbass, was ransacked by pro-Russian insurgents, who looted the building, destroyed surveillance equipment, and set it on fire.

[22] Mayor of Donetsk Oleksandr Lukyanchenko said the death toll in the clashes stood at forty, almost all of them separatist insurgents, as well as two civilians.

[7] 15–35[citation needed] of the insurgents were reportedly killed in a single incident when two lorries carrying wounded fighters away from the airport were ambushed in a friendly-fire incident by the Vostok Battalion, which confused them for Ukrainian forces[27][28][29] (separatist "prime minister" Aleksander Boroday announced that they had been ambushed by Ukrainian ground forces and hit by airstrikes).

[31] Among the dead on the pro-Russian side were former Russian Airborne Troops of the 45th regiment special forces,[31] Soviet–Afghan War veterans,[31] and world kick-boxing champion Nikolai Leonov who was a native of Dnipropetrovsk.