believe bashar al-assad's military conducted a sarin gas attack in april. investigators say it was 1 of 20 chemical attacks by syria over the past four years. syria has denied responsibility. lawmakers back from vacation are once again digging into russia's interference in last year's u.s. election. catherine herridge tells us some very high-profile witnesses are expected. >> susan rice, the obama former national security advisor, was behind closed doors for three hours taking questions from members of the house intelligence committee who ignored reporters questions. lawmakers want more insight into russian's election meddling as well as reiss' request to identify trump campaign associates. whether susan rice's decisions were driven by politics. committee republicans issued subpoenas for christopher wray and attorney general jeff sessions after their department