Even after Robert Reeder pleaded guilty to illegally picketing inside the U.S. Capitol building on Jan. 6, he remained adamant that he was innocent of the worst allegations leveled against him.

Prosecutors argued that Reeder actively participated in chants with rioters and egged on the aggressive crowd, though they could not show that he participated in any violence. They asked a federal judge to sentence him with a fine and prison time.

Reeder, a former FedEx driver from Maryland, told FBI agents that he was merely an “accidental tourist” who got swept up in the crowd. The 55-year-old denied engaging in or inciting violence, according to a sentencing memorandum his attorney filed earlier this month. He asked the judge for probation.

But new video from Jan. 6 that surfaced just before his sentencing hearing on Wednesday upended both sides of the case.

Prosecutors opened the Wednesday afternoon hearing by telling U.S. District Judge Thomas Hogan that they had learned of several videos that appeared to show Reeder allegedly physically grappling with a police officer. The prosecutors said they found the footage at 10:30 a.m. that day and requested more time to review the new evidence before sentencing, WRC-TV reporter Scott MacFarlane reported.

Hogan agreed and set a new hearing for Oct. 8, according to court records.

A group of online sleuths known by the moniker “Sedition Hunters” said on Twitter that it sent the footage to the FBI about four hours before the court hearing. The group also shared the videos on social media.

The clips show a man wearing what appears to be the same bright blue jacket, gray hoodie, disposable face mask and red Make America Great Again cap that prosecutors said Reeder wore on Jan. 6. The man appears to shove a police officer before the two engage in a brief scuffle. The man can also be seen behind barricades set up to keep the crowd away from restricted parts of the Capitol building grounds.

Many have argued that President Donald Trump's efforts amounted to an attempted coup on Jan. 6. Was it? And why does that matter? (Monica Rodman, Sarah Hashemi/The Washington Post)

An attorney for Reeder did not immediately respond to a request for comment from The Washington Post. After the video surfaced on Wednesday, Reeder’s lawyer said in court that “on first blush, the clip is problematic,” CNN reported.

The last-minute evidence may upend Reeder’s defense, which claimed that he had been unfairly grouped with violent far-right rioters.

In a sentencing memorandum, Reeder claimed that he merely walked into restricted parts of the Capitol to document what was happening “without violence — without destroying anything — without threats or without any other aggressive conduct.” He also denied an affinity with the rioters.

“Mr. Reeder is a registered Democrat, and was not a Trump supporter, although he did like the patriotic spirit that he believed that President Trump was trying to instill in Americans,” the court filing said.

But prosecutors flatly denied that portrayal in a response that described how Reeder ignored police instructions, alarms, barricades and even tear gas to illegally enter the Capitol. They argued that he filmed the rally because he was “a proud part of it,” according to court records.

“The Defendant’s sentencing memorandum attempts to paint a picture of the Defendant as a lost tourist, in awe of the Capitol, defending it from destruction and documenting the events of the day,” prosecutors said. “To believe the Defendant’s version of events one needs to suspend reality, ignore facts, and omit evidence.”

Prosecutors also filed exhibits that showed screenshots from Reeder’s social media accounts. In the months before the insurrection, Reeder shared frequent claims of election fraud and posts attacking prominent Democrats like Joe Biden and House Speaker Nancy Pelosi (D-Calif.).

A plea deal that Reeder agreed to allows prosecutors to bring new charges for “any crime of violence” discovered by investigators. Supplemental sentencing memorandums that may address the new video footage are due from both the prosecution and defense by Oct. 1, according to court records.