survey unions is picking up new signs of a significant buildup as russian planes ferry ships and troops and supplies. rebels are various persuasions and a ruthless isis mini state is also involved. the united states is warning moscow of a possible confrontation. let s turn to barbara starr. sheet getting more information. reporter: the u.s. has surprised by russia before just recall the russian takeover of crimea. this type the pentagon the state devil they are urge unitly trying to figure out how far moscow will go. as vladimir putin sense more military into syria. secretary of state john kerry making a second call to russian foreign minister sergei lavrov ratcheting up u.s. pressure.