washington top u.s. house representatives intelligence committee democrat say wednesday grave concern committee ability conduct credible investigation republican chairman suggest president donald trump communications may collect surveillance express grave concern chairman credible investigation conduct way u.s. representative adam schiff say statement house intelligence panel conduct one main congressional investigations possible tie trump associate russia 2016 u.s. president election republican representative devin nunes committee chairman announce news conference wednesday anonymous source provide information communications associate trump possibly trump sweep routine surveillance house democrat say republican undermine intel probe