fresh artillery strikes and finger-pointing along the border adding to already rising tensions. highlighting the critical moment, secretary of state blinken rushing to new york where he addressed the u.n. security council, describing how far he fears russia will go to create a pretext to invade, from fake images of mass graves to staged chemical weapons attacks, he says. so-called false flag operations, all while russia s claims of troop pullbacks are being dismissed in the west. in a moment, my interview with the u.s. ambassador to the united nations. but first, to ukraine and richard engel. reporter: today russia put out yet more video it says shows its forces pulling back from ukraine s borders. claims the u.s. slams as false. with president biden now warning the threat of a russian invasion is very high. it s very high. why? it s very because they have not they have not moved any of the troops out.