Donald Trump says he's a target of special counsel's criminal probe into 2020 election aftermath

Former President Donald Trump said in a social media post he's been informed by special counsel Jack Smith that he is a target of the criminal investigation into efforts to overturn the 2020 election, a sign he may soon be charged by the special counsel.

"Deranged Jack Smith, the prosecutor with Joe Biden's DOJ, sent a letter (again, it was Sunday night!) stating that I am a TARGET of the January 6th Grand Jury investigation, and giving me a very short 4 days to report to the Grand Jury, which almost always means an Arrest and Indictment," Trump posted on Truth Social.

Trump's attorneys, including Todd Blanche, received the target letter from Smith's team Sunday informing them that their client could face charges in the investigation into efforts to overturn the 2020 election, two sources familiar with what happened tell CNN.

A target letter from federal prosecutors to Trump makes clear that prosecutors are focused on the former president's actions in the investigation into overturning the 2020 election - and not just of those around him who tried to stop his election loss.

Trump's legal team has not formally responded to the invitation to testify before the grand jury, which the letter provides, but it is largely expected that Trump will decline to do so. The letter caught Trump's team off guard, who had not been anticipating Smith to potentially bring charges this month, or against Trump.

Trump's advisers spent Tuesday morning calling lawyers and allies, trying to figure out who else - if anyone - received a target letter related to the special counsel's investigation into the aftermath of the 2020 election, multiple sources familiar with the outreach told CNN. Trump's advisers are hoping to glean better insight into what a potential criminal case against the former president might entail, according to sources.

So far, Trump's team has not identified anyone else who got a target letter, the sources said.

Trump also received a target letter from Smith in May roughly three weeks before he was indicted in the investigation into the mishandling of classified documents.

Smith declined to comment Tuesday when asked by CNN about the target letter and whether his office is preparing to indict the former president. CNN spotted Smith leaving a Subway sandwich shop in Washington, DC.

The White House declined to comment. CNN has also reached out to Biden's reelection campaign for comment.

Trump has already been indicted twice this year. Manhattan District Attorney Alvin Bragg charged the former president on 34 counts of falsifying business records in March, and Smith charged Trump on 37 counts in the classified documents investigation last month. Trump pleaded not guilty in both cases.

Justice Department regulations allow for prosecutors to notify subjects of an investigation that they have become a target. Often a notification that a person is a target is a strong sign an indictment could follow, but it is possible the recipient is not ultimately charged.

Those notifications aren't required, but prosecutors have the discretion to notify subjects that they have become a target.

While Trump didn't say specifically why he was told to report to the grand jury, individuals who receive a target letter typically are given the chance to appear before a grand jury to present evidence or testify if they choose.

In the classified documents case, Trump received a target letter from the special counsel's office on May 19. His lawyers then met with Justice Department officials on June 5. Three days after that, on June 8, the grand jury returned an indictment against Trump and his co-defendant and aide Walt Nauta.

Trump himself has been compartmentalizing the news. The former president spent Monday at his Bedminster golf club with a few close advisers and is traveling to Iowa later Tuesday with a small group of his campaign team for a town hall with Fox News' Sean Hannity.

Trump reached out on Tuesday to some of his top allies on Capitol Hill - including House Speaker Kevin McCarthy and House GOP Conference Chair Elise Stefanik - to strategize how they're going to go on offense against the special counsel's investigation, according to sources familiar with the conversations.

Trump and Stefanik discussed her role on the House subcommittee on alleged weaponization of the federal government, as well as her overall efforts to rally support from the House GOP conference around the former president, according to a source familiar with the call.

Trump's allies on Capitol Hill quickly attacked the special counsel in the wake of the target letter. "I think the American public is tired of this," McCarthy said. "They want to have equal justice, and the idea that they utilize this to go after those who politically disagree with them is wrong."

Trump defended himself in his social media posts Tuesday morning.

"Under the United States Constitution, I have the right to protest an Election that I am fully convinced was Rigged and Stolen, just as Democrats have done against me in 2016, and many others have done over the ages," Trump wrote.

Smith has been investigating efforts to overturn the 2020 election leading up to the January 6, 2021, attack on the US Capitol, including putting forward fake electors in states Trump lost and a pressure campaign against his then-Vice President Mike Pence to try to overturn the election when Congress certified Joe Biden's Electoral College win on January 6.

The special counsel has also probed Trump's knowledge that he lost the 2020 election, pressure within the Justice Department to help with efforts to overturn the election and fundraising efforts after the election.

In addition, prosecutors have focused on a chaotic December 2020 Oval Office meeting in the final days of the Trump administration, in which Trump's advisers discussed seizing voting machines, naming a special counsel to investigate voter fraud and invoking martial law as part of the efforts to overturn the election.

The grand jury is continuing to hear from witnesses, and a close Trump adviser is expected to appear on Thursday in the special counsel's investigation into the aftermath of the 2020 election, two sources familiar with the matter tell CNN.

Will Russell, who has testified to the grand jury at least twice before, served as a special assistant to the president as well as deputy director of advance and trip director in the Trump White House. He has continued to work for Trump after he left office.

Russell's attorney declined to comment.

Dozens of witnesses have spoken to prosecutors and testified before the grand jury in the 2020 election investigation, including a lengthy list of top aides to Trump in the White House as well as Pence.

A number of Trump lawyers also have spoken to federal investigators. Last month, Trump's former attorney Rudy Giuliani met with investigators for a voluntary interview over two days that covered a range of topics, including the tumultuous December 2020 meeting that he attended, CNN previously reported.

Giuliani's lawyer, Robert Costello, told CNN that Giuliani has not received a target letter.

In recent months, federal prosecutors working for the special counsel have interviewed officials from all seven battleground states targeted by Trump and his allies as they sought to overturn the 2020 election results, CNN has learned.

Smith's team met with at least one official from the Nevada secretary of state's office in recent months as part of the ongoing criminal probe, according to a source familiar with the matter.

Prosecutors have also interviewed two Wisconsin election officials in recent months: Wisconsin Elections Commission Administrator Meagan Wolfe and Claire Woodall-Vogg, executive director of the Milwaukee Election Commission.

And Smith's team has contacted former Arizona Gov. Doug Ducey, who Trump pressured to overturn the 2020 election, a source familiar with the outreach confirmed to CNN.

A spokesman for Ducey confirmed the outreach from Smith's team, which has not been previously reported. "Yes, he's been contacted. He's been responsive, and just as he's done since the election, he will do the right thing," Ducey spokesman Daniel Scarpinato told CNN in a statement.

Other Arizona officials have also been interviewed and subpoenaed by the special counsel's team.

Trump narrowly lost Arizona to Biden by less than 11,000 votes in 2020. Trump publicly attacked Ducey, a former ally, over the state's certification of the results. As Ducey was certifying the election results in November 2020, Trump appeared to call the governor - with a "Hail to the Chief" ringtone heard playing on Ducey's phone. Ducey did not take that call but later said he spoke with Trump, though he did not describe the specifics of the conversation.

The grand jury investigating 2020 election interference is meeting Tuesday at the federal courthouse in Washington, DC.

This story has been updated with additional reporting and developments.

CNN's Alayna Treene, Zachary Cohen, Melanie Zanona, Matthew Philips and Aleena Fayaz contributed to this report.