The Cleveland jails are being emptied and its courts are staying open until 1 a.m. in case of mass arrests. Riot gear, handcuffs, body cameras — police equipment that cost tens of millions of dollars — are ready, and more than 70 law enforcement and government agencies are on alert…

The close proximity of thousands who love or loathe Trump is what law enforcement is most worried about. The fact that Ohio has an open-carry law, allowing people to walk into crowds carrying a rifle if they have a permit, compounds safety concerns…

City officials said many people who had planned to see the activity surrounding Cleveland’s first political convention in 80 years are now choosing to stay away. Some hotels now have vacancies after last- ­minute dropouts. And, some protesters are deciding not to come, including some visited recently by the FBI…

At least half a dozen of the most prominent Black Lives Matter leaders — in San Francisco, St. Louis, the District and Charlotte, among other places — have been contacted by the FBI in recent days. That comes after local activists, associated with the protest movement and other causes, were also contacted by federal agents…

“The agent basically told me not to go to Cleveland,” said Sam Sinyangwe, an activist in San Francisco with Campaign Zero, a police reform group, who said an agent came to his home this week.