CLEVELAND: Donald Trump trained his fire Saturday on the protesters disrupting his rallies, branding them “thugs” and extremists, as White House rivals warned the Republican’s heated rhetoric was dangerously fanning tensions. Democratic frontrunner Hillary Clinton issued a stern warning a day after a Trump rally in Chicago was called off amid scenes of violence, with days to go until a crucial round of nomination votes Tuesday. “If you play with matches, you’re going to start a fire you can’t control. That’s not leadership, that’s political arson,” Clinton said. But Trump dismissed the notion his extreme statements on immigrants and Muslims had exacerbated tensions, placing the blame squarely on “organized thugs” as he returned to his theme over and over on the campaign trail Saturday.