U.S. official calls buildup of Russian forces near Ukraine border "concerning"

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 his country's parliament on Tuesday that Russian troops from different regions have been assembling near the border. One possible explanation is that the troops are training, but the American defense official said Russia had not announced any exercises in the area.