US intel assesses Russian operatives behind fake video trying to smear Tim Walz CNNU.S. intel officials say Russia is behind attempts to smear Tim Walz NPRRussian disinformation groups promoting false claims about Gov. Tim Walz, experts say CBS NewsU.S. officials say Russia smeared Tim Walz, might stoke post-vote violence The Washington PostRussia behind Walz video, US intelligence community officials say Fox News