A massive police response mobilized outside a fenced-off U.S. Capitol Saturday morning to greet a group of right-wing protesters who insist their noon demonstration won’t descend into violence.

Advocates at the "Justice for J6" rally in Washington, D.C., plan to denounce what they call the "inhumane treatment" of dozens of Jan. 6 rioters who remain jailed while awaiting trials that are still months away.

Two hours ahead of the rally, a fleet of District of Columbia-owned dump trucks lined up to block the city’s streets off from roaming demonstrators, and an olive-green Humvee from neighboring Prince George’s County, Maryland, was stationed outside the Capitol’s Botanic Garden Conservatory.

CAPITOL POLICE BRACING FOR ‘JUSTICE FOR J6’ RALLY IN SUPPORT OF JAN. 6 ALLEGED RIOTERS

Counter-protesters arrived early, bearing giant flags in support of Black Lives Matter and trans rights, and a banner mimicking Trump’s signature campaign branding that read "Loser." A hand-lettered sign identified the bearer as "proud Antifa scum."

Capitol Police, nervous about a reprise of the January chaos that led to five deaths, requested reinforcements from the Pentagon this week to fend off any attacks from rally-goers. A company of 100 National Guard troops was expected to patrol the event.

On Wednesday, federal workers reinstalled the tall, black security fencing that had been removed in July.

"We’ve cooperated with the Capitol Police, Park Police, Metropolitan Police," Matt Braynard of Look Ahead America, the rally’s main sponsor, told Fox5 this week. "We’ve got … a diplomatic security team to help make the event be smooth."

The group issued a statement Friday to "condemn political violence in all its forms, especially violence perpetrated on January 6."

"This is a rally in support of those who have been charged with nonviolent offences to protest of their disparate treatment at the hands of the Department of Justice and the Judiciary," the statement read.

Demonstrators hold signs near members of the media before a rally near the U.S. Capitol in Washington, Saturday, Sept. 18, 2021. The rally was planned by allies of former President Donald Trump and aimed at supporting the so-called "political prisoners" of the Jan. 6 insurrection at the U.S. Capitol. (AP Photo/Brynn Anderson) (AP Photo/Brynn Anderson)

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Braynard’s group claims that 67 of the 595 people who have been charged with assault, obstruction, trespassing and other crimes in connection with the Capitol incursion remain behind bars — many in solitary confinement — as their trial dates are repeatedly delayed.

Two GOP congressional candidates — Joe Kent of Washington state and Mike Collins of Georgia — were set to address the crowd.

Braynard, a former Trump campaign strategist who boosted his public profile with allegations of voting anomalies during the 2020 presidential election, instructed rally-goers not to bring any political gear — either in favor of former President Donald Trump or in opposition to President Biden — to the event.

"Anyone not honoring this request will be assumed to be an infiltrator," he tweeted this week.

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Trump on Thursday dismissed the demonstration as "a setup."

"If people don’t show up they’ll say, ‘Oh, it’s a lack of spirit,’" he told The Federalist. "And if people do show up they’ll be harassed."

But he also expressed support for "the people being persecuted so unfairly relating to the January 6th protest" in a statement issued by his Save America PAC this week.

"In addition to everything else, it has proven conclusively that we are a two-tiered system of justice," Trump wrote. "In the end, however, JUSTICE WILL PREVAIL!"

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