(NewsNation) — Former President Donald Trump said Tuesday he received a letter stating he is a target of a grand jury investigation into the Jan. 6 Capitol riot.

It’s an indication he could soon be indicted by federal prosecutors.

Trump wrote on Truth Social that he was with his family after a Turning Point event in Florida on Sunday night when he got the news.

Special counsel Jack Smith, whose office is leading the investigation, gave Trump a letter giving him “a very short 4 days to report to the Grand Jury,” the former president claimed.

A spokesman for Smith declined comment to the Associated Press.

“THIS WITCH HUNT IS ALL ABOUT ELECTION INTERFERENCE AND A COMPLETE AND TOTAL POLITICAL WEAPONIZATION OF LAW ENFORCEMENT,” Trump said on Truth Social.

Last year, a House Committee probing the events surrounding Jan. 6 recommended criminal charges against Trump. However, this criminal referral was mostly symbolic.

White House Press Secretary Karine Jean-Pierre declined to comment on this particular case, only saying President Joe Biden respects the Department of Justice and its independence.

A number of people have been questioned by Smith’s team as they look into efforts by Trump and his associates to block the transfer of power to Biden after the 2020 election in the days leading up to the Jan. 6 riot.

Prosecutors questioned former Vice President Mike Pence, former Trump lawyer Rudy Giuliani and local election officials in states including Michigan and New Mexico.

The probe by Smith’s team has focused on the role Trump’s lawyers played in pressing for the overturn of election results, as well as plans for slates of fake electors in states Biden won to submit electoral certificates to Congress.

Trump has denied any wrongdoing.

Speaking at a South Carolina news conference where he unveiled his military policy, Florida Gov. Ron DeSantis, who is seen as Trump’s main rival, declined to say what he thought about the letter in particular. However, DeSantis did criticize what he called the “politicization” of the Justice Department.

DeSantis did say, though, that it was shown Trump was in the White House on Jan. 6 and “didn’t do anything” as the riots unfolded.

“He should have come out more forcefully, of course,” DeSantis said.

Letters like the ones Trump says he’s received this week can be used to advise people that prosecutors have evidence linking them to a crime. Trump previously received one before being charged in a different federal investigation into his alleged mishandling of classified documents.

Prosecutors, in an indictment for that case, included evidence of these documents being stored in areas of Trump’s Mar-a-Lago estate potentially open to the public. They also detailed two times Trump reportedly showed these materials to unauthorized persons.

Trump has pleaded not guilty to these charges.

Meanwhile, in Georgia, Fulton County District Attorney Fani Willis’ office has been investigating whether Trump and his allies broke any laws while trying to overturn his 2020 loss in the state.

Considered the front-runner in the 2024 GOP presidential race, Trump will be in Iowa Tuesday for a town hall with Fox News’ Sean Hannity.

The Associated Press contributed to this story.