Government troops clashed with armed activists at the airport in Ukraine's eastern city of Donetsk Monday, one day after presidential elections were held in the country.
Smoke billowed after fighter jets were seen flying over and explosions were heard, Xinhua reported.
Armed activists in the eastern Donetsk and Lugansk regions established the "people's republic" in early April and an overwhelming majority of voters favoured their regions' independence at referendums held May 11.
Kiev has rejected the referendums as illegal and launched "anti-terrorist operations" in the regions.