Heavy fighting broke out on May 26 at the international airport in the eastern Ukrainian city of Donetsk, a major foothold for pro-Russian separatists. After reports early in the day said gunmen had stormed the airport and forced its closure, Ukrainian troops rushed to the scene. Explosions and gunfire erupted, sending smoke into the skies as the fighting continued. Fighter aircraft were also deployed to the scene. With the battle still raging, AFP reported that Ukrainian security forces had attacked after a deadline to the separatist occupiers expired.