U.S. defense official notes "concerning" buildup of Russian forces near Ukraine

There is "concerning" buildup of Russian forces near the border with Ukraine, according to a U.S. defense official.

Ukrainian Commander-In-Chief Ruslan Khomchack told parliament Tuesday that Russian troops from different regions have been assembling near the Russia-Ukraine border. One possible explanation is that troops there are training, but the defense official said Russia had not announced exercises in that area.