COLUMBUS, Ohio (AP) — As Donald Trump seeks to unify the fractured GOP around his presidential candidacy, protest groups will gather outside the Republican National Convention to raise their voices on issues from the party's nominee and agenda, to immigration reform and poverty, and race relations and police accountability. Authorities anticipate spontaneous gatherings during the four-day event and are worried about the threat of violence. Homeland Security Secretary Jeh Johnson said he's concerned that demonstrations may get out of hand, especially in the wake of recent police shootings of black men and the ambush that killed five police officers in Dallas. Roughly 4,000 U.S.