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>> thanks very much, jim sciutto, for that report. jim will be back later. u.s. officials report no major moves by russian forces either in ukraine or inside russia but they say russian troops carry out massive war games this week under the gaze of the russian president p vladimir putin are still in the field, most have not returned to their barracks. at the same time the pentagon is taking concrete new steps to try to address the crisis. lets bring if our pentagon correspondent barbara starr....