Reuters tells us:

 U.S. prosecutors flagged a threatening social media post from Donald Trump in a late-night court filing on Friday, arguing that it suggests he might intimidate witnesses by improperly disclosing confidential evidence received from the government.

On his Truth Social site, the former president wrote, “IF YOU GO AFTER ME, I’M COMING AFTER YOU!” on Friday afternoon, a day after he pleaded not guilty to charges that he orchestrated a criminal conspiracy to try to reverse his 2020 election loss to Democrat Joe Biden.

In the filing in Washington federal court, the office of Special Counsel Jack Smith said Trump’s post raised concerns that he might publicly reveal secret material, such as grand jury transcripts, obtained from prosecutors.

Under the process known as discovery, prosecutors are required to provide defendants with the evidence against them so they can prepare their defense.

“It could have a harmful chilling effect on witnesses or adversely affect the fair administration of justice in this case,” prosecutors wrote, noting that Trump has a history of attacking judges, attorneys and witnesses in other cases against him.

At his arraignment on Thursday, Trump swore not to intimidate witnesses or communicate with them without legal counsel present.

And then promptly issued a threat. On social media.