>> we'll identify traffic that are not operating within international rules ask regulations that might infringe on nato airspace. >> reporter: bolstering the border against an increasingly boisterous neighbor. that's the american squadrone ron's first intercept since they arrived last week. their deployment, along with moving more u.s. forces to eastern europe, is part of an overall mission to reassure nato allies and deter russian aggression. weijia. >> jiang: charlie d'agata in estonia, thank you. tonight, a crack in the republican party is widening. the roan continues to side with former president trump, but former vice president mike pence is finally calling out his false election claims,s and late last night, trump fired back. we get more now from cbs' christina ruffini who is at the white house. christina, good evening. >> reporter: good evening, weijia. well, mr. trump just issued