Burned before, Capitol Police say they are taking no chances as they prepare for a Saturday rally at the U.S. Capitol in support of rioters imprisoned after the violent Jan. 6 insurrection.

Though it is unclear how big the rally will be, the Capitol Police and Metropolitan Police Department are fully activating in an effort to avoid a repeat of the pre-inauguration attack. Underprepared police were overwhelmed as hundreds of President Donald Trump’s supporters broke into the Capitol and interrupted the certification of Joe Biden’s victory.

Capitol Police Chief Tom Manger said at a news conference Friday it was difficult to say whether threats of violence at the event are credible, but he said that “chatter” online and elsewhere has been similar to intelligence that was missed in January.

A permit for the protest allows 700 people. Manger said he believes the most likely possibility for for violence Saturday will involve clashes between the protesters and counter-protesters who may show up.

“We’re not going to tolerate violence, and we will not tolerate criminal behavior of any kind,” Manger said. “The American public and members of Congress have an expectation that we protect the Capitol. And I am confident that the plan we have in place will meet that expectation.”

After multiple missteps in January, law enforcement is out in full force. The fence around the Capitol is back up, temporarily. Police are preparing for the possibility that some demonstrators may arrive with weapons. The D.C. police department is at the ready, and U.S. Capitol Police have requested assistance from nearby law enforcement agencies.

The rally, organized by former Trump campaign strategist Matt Braynard, is aimed at supporting people who have been detained after the Jan. 6 insurrection — about 60 people held behind bars out of the more than 600 charged in the deadly riot. It’s the latest attempt to downplay and deny the January violence.

Illinois Rep. Adam Kinzinger, one of two Republicans serving on a House committee investigating the January attacks, said he supports the aggressive law enforcement efforts.

“Hopefully the overreaction of law enforcement is actually the thing that can keep this from getting out of hand,” Kinzinger said in an interview Thursday. He predicted that people will criticize the effort if the protest is small and nonviolent, “but that’s what needs to happen because January 6th obviously was an underreaction and it escalated.”

Intelligence collected ahead of Saturday’s rally has suggested that extremist groups such as the Proud Boys and Oath Keepers will turn up. But some prominent members of the groups have sworn they aren’t going and have told others not to attend. Far-right online chatter has been generally tame, and Republican lawmakers are downplaying the event.

Defense Secretary Lloyd Austin approved a request for about 100 members of the D.C. National Guard to be stationed at a city armory near the Capitol, to be called if needed as backup for other law enforcement agencies. They will primarily protect the Capitol building and congressional offices. They’ll be without firearms, but will be equipped with batons and protective vests for self-defense.

Meanwhile, a Homeland Security intelligence report warned of social media posts that discussed possibly storming the Capitol the night before the rally. One user also “commented on kidnapping an identified member of Congress,” the document said, though the lawmaker wasn’t identified by name in the report. No lawmakers were expected to be in the building Saturday, as Congress is out of session.

“Other references to violence identified on social media include discussions of using the rally to target local Jewish institutions, elected officials, and ‘liberal churches,'” the intelligence report said.

Many commenters on online platforms popular with the far right like Telegram disavowed the rally, saying they believed law enforcement was promoting the event to entrap Trump supporters. Some urged their followers not to attend what they said was a “false flag” event they believed was secretly organized by the FBI.

At the same time, however, some commenters continued to promote rallies planned for Saturday in cities and state capitals across the country.

In a notice to House members this week, Sergeant at Arms William Walker urged lawmakers to stay away from the Capitol complex on Saturday. And lawmakers who supported Trump’s efforts to overturn his election defeat distanced themselves from the event.

“I don’t know what it is,” said Texas Sen. Ted Cruz said when asked about the rally.

Trump is still using his platform as the most popular leader in the GOP to express sympathy for those who were arrested and continue spreading election misinformation. In a statement Thursday, he said: “Our hearts and minds are with the people being persecuted so unfairly relating to the January 6th protest concerning the Rigged Presidential Election.”

The Associated Press reviewed hundreds of court and jail records for the Capitol riot defendants to uncover how many were being detained and found about 60 held in federal custody awaiting trial or sentencing hearings. Federal officials are still looking for other suspects who could also wind up behind bars. Just Friday, a judge ordered the pretrial detention of a Pennsylvania woman who contends the court doesn’t have jurisdiction over her.

At least 30 are jailed in Washington. The rest are locked up in facilities across the country. They have said they are being treated unfairly, and one defendant said he was beaten.

Federal authorities have identified several of those detained as extremist group leaders, members or associates, including nine defendants linked to the Proud Boys and three connected to the antigovernment Oath Keepers. Dozens are charged with conspiring to mount coordinated attacks on the Capitol to block Congress from certifying the 2020 Electoral College vote, among the most serious of the charges.

Some jailed defendants are charged with assaulting police officers, others with making violent threats. A few were freed after their arrests but subsequently detained again, accused of violating release conditions.

The U.S. Court of Appeals for the District of Columbia Circuit has set standards for judges to apply in deciding whether to jail a Capitol riot defendant. A three-judge panel of the appeals court ruled in March that rioters accused of assaulting officers, breaking through windows, doors and barricades, or playing leadership roles in the attack were in “a different category of dangerousness” than those who merely cheered on the violence or entered the building after it was breached.