Former US president Donald Trump used the first public appearance since his federal indictment to ratchet up attacks on the Justice Department, accusing prosecutors, without evidence, of a politically motivated campaign to keep him from the White House.
Speaking at Georgia's state Republican convention, Mr Trump alleged that President Joe Biden, a Democrat, orchestrated the criminal charges in order to undermine his main political rival's presidential campaign.
There is no evidence to support Mr Trump's allegations.
The Justice Department maintains that all its investigative decisions are made without regard to partisan politics, and Biden has said he would not get involved in the Trump probe.
"The ridiculous and baseless indictment of me by the Biden administration's weaponised department of injustice will go down as among the most horrific abuses of power in the history of our country," Trump told the crowd of local party officials.
"This vicious persecution is a travesty of justice."
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Prosecutors allege the former president held on to materials, including documents about the US nuclear programme and domestic vulnerabilities to a potential attack, that he knew he should not have retained.
The 49-page indictment also detailed two instances in which Mr Trump allegedly shared classified information with people not authorized to receive it, as well as efforts to obstruct government investigators seeking to retrieve the materials.
The indictment of a former US president on federal charges is unprecedented in American history and came as Mr Trump is the clear front-runner for the Republican presidential nomination next year.
The charges ensure the case will be a focal point of the party's nomination contest.
Most of Mr Trump's rivals responded by accusing the Justice Department of political bias, reflecting their fears of upsetting Mr Trump's core supporters, a group thought to be 30% of the Republican electorate.
He is due to make a first appearance in the case in a Miami court on Tuesday, a day before his 77th birthday.
Calling it a "joke of an indictment," Mr Trump told the audience in Georgia the prosecution would further bolster his support within the party, similar to how charges in New York in March over hush-money payments elevated his ranking in primary polls.
"The only good thing is it's driven my poll numbers way up," he said.
