Russia has made incursions near two towns key to army supply routes in eastern Ukraine, a Ukrainian military official said on Wednesday, as Moscow seeks a breakthrough in a summer offensive at a time of uncertainty over U.

Vladimir Putin’s troops are using smaller units to attack the front lines and Ukraine is being forced to respond.

KYIV, Ukraine -- An emboldened Russia has ramped up military offensives on two fronts in Ukraine, scattering Kyiv’s precious reserve troops and threatening to expand the fighting to a new Ukrainian region as each side seeks an advantage before the fighting season wanes in the autumn.