At least 30 people have been killed in a Russian glide bomb attack on two civilian buses in the eastern front line city of Kramatorsk, rescue officials say. Authorities said three people were also killed in the village of Bilenke, part of the Kramatorsk community. Another 18 people were wounded, said Donetsk regional head Vadym Filashkin, accusing Russia of targeting buses carrying passengers to kill as many civilians as possible. Kramatorsk and neighbouring Slovyansk are part of a so-called fortress belt that Moscow is trying to seize as part of Russian President Vladimir Putin's claim to the entire Ukrainian industrial region of Donbas.