Only hours after Petro Poroshenko was announced the winner of Ukraine's presidential elections, the worst violence of the two month long crisis in eastern Ukraine exploded at Donetsk' Sergei Prokofiev airport. Early Monday morning, gunmen of the Donetsk Peoples Republic arrived at the airport and took over the terminal building, prompting the Ukrainian military based there to issue an ultimatum to the rebels to lay down their weapons and leave. A massive firefight broke out which both fighter jets and attack helicopters were used by the Ukrainian military. The sound of gunfire and explosions filled the air as rebels and journalists ducked for cover along the access road to the airport terminal.