The House Intelligence Committee met behind closed doors in March on Capitol Hill. The committee is conducting one of several investigations of Russian attempts to interfere in the U.S. presidential election. Monday, former Obama administration officials are set to testify at a Senate Judiciary subcommittee hearing. Mark Wilson/Getty Images hide caption
Ukrainian investigators are seeking to understand the extent of the ties Paul Manafort, shown here in July 2016, had with former Ukrainian President Viktor Yanukovych. Carolyn Kaster/AP hide caption
Devin Nunes, R-Calif., chairman of the House Intelligence Committee, speaks to the media about the investigation of Russian meddling in the 2016 presidential election on Capitol Hill in Washington, D.C., on Friday. Nicholas Kamm/AFP/Getty Images hide caption
Former Donald Trump campaign chairman Paul Manafort, seen here last June, was paid millions of dollars to advance a pro-Russian agenda, the AP reports. Drew Angerer/Getty Images hide caption
Corey Lewandowski listens (at left) as Donald Trump speaks at a campaign news conference in Palm Beach, Fla., earlier this year. Gerald Herbert/AP hide caption