KIEV - Ukraine's military said on Sunday pro-Russian rebels had shelled Ukrainian positions on ten separate occasions since a ceasefire came into effect at midnight."As of the morning of February 15, there have been ten shelling attacks on our positions by rebels - mainly in the area of Debaltseve," spokesman Anatoly Stelmach said by telephone.A Reuters witness in east Ukraine heard the sound of heavy artillery coming from the direction of Debaltseve, a key transport hub where government forces have been hard pressed by encircling separatists.
