Top U.S. national security officials said they’re worried about the potential for violence at the national political conventions that start next week, especially the challenge of holding the Republican event in a state that gives citizens the right to carry firearms openly.

"I am concerned about the prospect of demonstrations getting out of hand," Homeland Security Secretary Jeh Johnson told the House Homeland Security Committee during a hearing in Washington Thursday. "I am concerned about the possibility of violence."



Agents with the Federal Bureau of Investigation will be watching the conventions "very, very carefully" because they’re events that draw protesters from "across the spectrum," including radical groups, FBI Director James Comey said during the hearing.

The Republican convention in Cleveland presents a unique challenge because of an Ohio state law allowing citizens to carry firearms in the open, Johnson said. "Ohio is an open-carry state," he said. "It does present a challenging situation."

Recent Protests

The convention in Cleveland, where Donald Trump is set to accept the Republican presidential nomination next week, has been preceded by protests in several U.S. cities against police violence organized by groups such as Black Lives Matter in which hundreds of demonstrators have been arrested. A mostly peaceful protest in Dallas on July 7 took a deadly turn when 25-year-old Micah Johnson shot and killed five police officers and wounded almost a dozen others.

During the presidential primaries, shoving and fistfights sometimes erupted at Trump’s rallies between supporters and protesters.

The Democratic National Convention, where Hillary Clinton is to be nominated, will be held in Philadelphia from July 25 to 28.

The Homeland Security Department will deploy about 3,000 personnel to each convention, including officials from the Transportation Security Administration, Coast Guard and Customs and Border Protection, Johnson said. More than 1,000 other U.S. government personnel will also be on hand as well as “probably thousands in terms of state and local law enforcement.”

At a hearing examining terrorist threats to the U.S. more broadly, Johnson said his biggest concern is an individual who quietly and quickly becomes self-radicalized over the internet to carry out an attack with little warning.

"The prospect of another attack by a self-radicalized actor -- somebody inspired by a foreign terrorist organization -- is the threat that most keeps me up at night," he said. "That is a new threat that we weren’t dealing with on a regular basis" several years ago.