You're reading: New York Times: Fears rise as Russian military units pour into Ukraine

Tanks and other military vehicles pouring over the border from Russia into eastern Ukraine. Nightly artillery battles in the region's biggest city, Donetsk, and reports of fighting around another regional capital. And now, sightings of the “green men,” professional soldiers in green uniforms without insignia, the same type of forces that carried out the invasion of Crimea last spring. 

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