Trump has posted his mug shot on his X account, marking his first post on the social media platform since Jan. 8, 2021.

Trump was suspended from X -- then known as Twitter -- following the attack on the U.S. Capitol on Jan. 6, 2021. He hadn't tweeted since new owner Elon Musk reinstated his Twitter account in November 2022 -- instead using his Truth Social platform to post messages.

Trump posted his mug shot on Truth Social as well.

Both posts linked to Trump's 2024 campaign website, where the mug shot was also used as part of a fundraising pitch.

-ABC News' Soo Rin Kim, Lalee Ibssa and Will Steakin

The Fulton County Sheriff's Office has released the mug shot taken of Trump during his processing this evening.

This is the first mug shot to be taken of Trump among his four indictments.

In remarks before boarding his plane at Hartsfield-Jackson Atlanta International Airport, Trump said he had the right to challenge an election "we think is dishonest."

"We did nothing wrong," said Trump, continuing to falsely claim that the election had been stolen.

"We have every right to challenge the election," he said.

Trump's plane is now en route to Newark Liberty International Airport.

Trump's motorcade is now en route to Hartsfield-Jackson Atlanta International Airport following his booking and release from the Fulton County Jail.

Shawn Still, a recently elected Georgia state senator who was one of the so-called "fake electors" accused in the DA's indictment of working to overturn the 2020 election results in Georgia, has filed a motion seeking to move his case to federal court -- making him the fourth defendant in the case to do so.

Former Trump Chief of Staff Mark Meadows, former DOJ official Jeffrey Clark, and former Georgia GOP chair David Shafer all previously filed their own motions seeking removal to federal court.

Although Still is not a federal official, his motion argues that he "was acting, or was acting under, an officer of the United States" in his role as an alternate elector -- a similar argument to Shafer's motion.

"That is, the role of presidential elector is a federal one -- created and directed by the United States Constitution and Congress. Thus, Mr. Still, acting as a presidential elector, was a federal officer," Still's filing says.

Still's filing also argues that he was following the advice of authorities on the matter, saying, "Mr. Still, as a presidential elector, was also acting at the direction of the incumbent President of the United States. The President's attorneys instructed Mr. Still and the other contingent electors that they had to meet and cast their ballots on December 14, 2020, in order to preserve the presidential election contest."

Still is charged with eight counts in the indictment, including impersonating a public officer and forgery in the first degree.