Capitol Police memo warns of potential for violence during September 18 rally

(CNN)Law enforcement officials are bracing for potential clashes and unrest during an upcoming right-wing rally in Washington, DC, as violent rhetoric surrounding the September 18 event has increased online and counterprotests are being planned for the same day, according to an internal Capitol Police memo reviewed by CNN. The latest intelligence report on the "Justice for J6" rally — which aims to support insurrectionists charged in the Capitol riots — notes that online chatter in support of the event started increasing after the officer who fatally shot rioter Ashli Babbitt went public with his identity in a recent interview with NBC's Lester Holt. There's been a noticeable uptick in violent rhetoric around the event and heated discussions centered on Babbitt's shooting on social media and discussion boards, according to the memo. The document warns that many individuals may also see September 18 as a "Justice for Ashli Babbitt" rally, which could be cause for concern, and it's not unreasonable to plan for violent altercations. There have been additional discussions of violence associated with the event, with one online chat suggesting violence against Jewish centers and liberal churches while law enforcement is distracted that day. The Capitol Police plan to present their security plans for the rally to the Capitol Police board this week, according to a congressional source, but it's still unclear if that will entail bringing back the temporary fencing around the complex though that has been something under discussion and remains a possibility. The department is also "is working with Capitol region law enforcement partners and other law enforcement agencies," the source said, while the Metropolitan Police Department plans to be fully activated that weekend. House Speaker Nancy Pelosi has invited Senate Majority Leader Chuck Schumer, Senate Minority Leader Mitch McConnell and House Minority Leader Kevin McCarthy for a security briefing in her office Monday morning with US Capitol Police Chief Tom Manger to discuss security preparations for the rally, according to a source familiar. The top Democrat and Republican lawmakers on the House Administration Committee are also expected to receive separate security briefings in the coming days, another source said. During her weekly news conference on Wednesday, Pelosi declined to get into specifics on what security measures will be in place that day, but told reporters, "We intend to have the integrity of the Capitol be intact."

With concerns mounting on Capitol Hill about the rally -- and the community already on edge after multiple deadly incidents and bomb scares this year -- former FBI Deputy Director Andrew McCabe has warned that law enforcement needs to take the rally "very seriously."

"I think they should take it very seriously. In fact, they should take it more seriously than they took the same sort of intelligence that they likely saw on January 5," McCabe, a CNN contributor, told CNN's Poppy Harlow on "Erin Burnett OutFront" earlier this week.

Matt Braynard, the lead organizer of the rally, said there would be no violence coming from his group and that the event would be peaceful. Braynard also tweeted on Wednesday that all members of Congress are welcome to speak at the rally.

"This is a completely peaceful protest," he said in a Skype interview with CNN's Jessica Schneider. "And we have told people that when they come, we don't want to see any messaging about the election, we don't want to see any messaging on T-shirts and flags or signs about candidates or anything like that."

Around 500 people have indicated they plan to attend, though the memo notes that past recent events organized by this same group, Look Ahead America, had significantly lower attendance than expected and were peaceful. The rally is also taking place on a Saturday while the US House of Representatives is on recess, and there have been no noticeable increases in hotel reservations for that weekend, according to the memo.