When former President Donald Trump attended an event in the East Room of the White House, on July 7, 2020. [AP Photo]

Former U.S. President Donald Trump was on the attack Monday, assailing a Georgia prosecutor presenting evidence against him to a grand jury about his efforts to overturn his 2020 reelection loss in the southern state while at the same time taunting the judge in Washington overseeing the federal election interference case he is facing.

After a 2 -year investigation, Fulton County District Attorney Fani Willis started calling witnesses before a grand jury Monday in Atlanta to hear evidence of how Trump allegedly illegally attempted to upend his narrow loss to Democrat Joe Biden in Georgia, a pivotal battleground election state.

On his Truth Social media site Monday, Trump said in all caps, "Would someone please tell the Fulton County grand jury that I did not tamper with the election. The people that tampered with it were the ones that rigged it, and sadly, phoney [sic] Fani Willis, who has shockingly allowed Atlanta to become one of the most dangerous cities anywhere in the world, has no interest in seeing the massive amount of evidence available, or finding out who these people that committed this crime are."

"She only wants to 'get Trump,'" he wrote. Trump said he would "be happy" to give evidence to the grand jury, although in months of criminal investigations targeting him, he has turned down all offers to testify.

Willis has focused her investigation on Trump and a dozen or more of his political allies and could indict them this week on charges of attempting to interfere with the election outcome. The case against Trump in the state stems broadly from his taped phone call in early 2021 to state election officials soliciting them to "find" him 11,780 votes, one more than Biden's margin of victory.

It was the first time a Republican presidential candidate had lost the state since 1992. Georgia was one of several states where Trump narrowly lost and unsuccessfully sought to reverse the result, even as dozens of judges ruled against his election fraud claims.

To this day, he falsely contends that election irregularities cost him another term in the White House, though he leads the contest among Republican voters for the party's 2024 presidential nomination by a wide margin.

Trump also attacked Georgia's former Republican Lieutenant Governor Geoff Duncan, who said over the weekend that he had been summoned to testify before the grand jury Tuesday. He also had rebuffed Trump's efforts to help overturn his loss in the state. Trump, while misspelling Duncan's name, called him "a nasty disaster for those looking into the election fraud that took place in Georgia."

In the Washington case, Justice Department special counsel Jack Smith has accused Trump in a four-count indictment of scheming with six unnamed co-conspirators to illegally upend his national reelection loss.

The jurist randomly assigned to oversee the case, U.S. District Judge Tanya Chutkan, warned Trump last Friday to refrain from "inflammatory" attacks against people involved in the case, mainly to prevent intimidation of witnesses or influence possible jurors.

Trump assailed her early Monday on Truth Social, calling her "highly partisan" and "very biased and unfair."

"She obviously wants me behind bars," Trump wrote.

He cited a statement Chutkan made as she sentenced a woman who participated in the mob of Trump supporters that breached the U.S. Capitol on January 6, 2021, seeking to block Congress from certifying that Biden had won the November 2020 election.

As Chutkan sentenced Christine Priola of the Midwestern state of Ohio to 15 months in prison, the judge said, "I see the videotapes. I see the footage of the flags and the signs that people were carrying and the hats that they were wearing, and the garb."

"And the people who mobbed that Capitol were there in fealty, in loyalty to one man, not to the Constitution, of which most of the people who come before me seem woefully ignorant; not to the ideals of this county and not to the principles of democracy," the judge said. "It's blind loyalty to one person who, by the way, remains free to this day."

Chutkan warned Trump's lawyers at the Friday hearing that his defense should be mounted in the courtroom and "not on the internet," although it was unclear what action, if any, she might take against him for his Truth Social comment about her.

Aside from the investigation in Georgia and the election interference case in Washington, Trump is facing two other indictments. Smith accused him in Florida of illegally hoarding highly classified national security documents as he left the White House in early 2021, while a New York state prosecutor has indicted Trump on charges of altering business records to hide a hush money payment to a porn film star ahead of his successful 2016 run for the presidency.

He has denied wrongdoing in all four cases.