The U.S. State Department has called on Russia to withdraw its forces from Donbas.

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"May was the bloodiest month this year for Ukrainian soldiers defending their country against Russian aggression: ten killed and 91 wounded. The United States stands with Ukraine and calls on Russia to withdraw its forces from the Donbas," Spokesperson for the U.S. Department of State Heather Nauert wrote on Twitter on June 8, 2018.

As UNIAN reported earlier, Russia's hybrid military forces mounted 37 attacks on Ukrainian army positions in Donbas in the past 24 hours, with four Ukrainian soldiers reported as wounded in action.