The extent of Paul Manafort’s alleged involvement in ghostwriting an op-ed favorable to him has become much clearer from a new court filing submitted by Special Counsel Robert Mueller’s team Friday afternoon and emails about the op-ed provided to TPM by the man who claims to be its author: a former Ukrainian government publicist, Oleg Voloshyn.

Prosecutors are now accusing Manafort of not being forthright in his explanation to the court of an op-ed they alleged he was involved in ghost-writing, in violation of the judge’s gag order in the case.

“Manafort cannot bring himself to state that he had a role in drafting the op-ed, although that fact is established by irrefutable evidence,” prosecutors argued, referring to a court filed by Manafort’s attorney Thursday that contended he did not violate the court’s gag order. “And he does not disclose that the ostensible author of the op-ed has falsely represented to the government—and now the public—that Manafort did not write the op-ed.”

Manafort was indicted along with his protege Rick Gates in October on 12 counts including money laundering and tax fraud. They have both pleaded not guilty.

As recently as Dec. 4, according to the emails obtained by TPM, Manafort was working through a proxy with Voloshyn on an opinion piece submitted to an English-language newspaper in Ukraine—though in the emails, he is said to have “legal questions that are worrying him.”

Mueller claimed that Manafort had “parse[d” the language of the court’s gag order in order to defend his participation in the op-ed, while arguing that if Manafort thought the order was ambiguous, he could have asked for the court’s permission before participating in the drafting of the op-ed.

To establish Manafort’s involvement in the op-ed —which sought to defend his lobbying work in Ukraine — Mueller included the edits prosecutors claimed Manafort made to the draft sent to him by Konstantin Kilimnik, a longtime business partner in Eastern Europe. Mueller also provided talking points said to be drafted by Gates in 2016 that “are mirrored in the op-ed piece [Manafort] substantially drafted.”

“Even taken in the light most favorable to Manafort, this conduct shows little respect for this Court and a penchant for skirting (if not breaking) rules.” Mueller said.

Voloshyn exchanged emails several times with TPM on Thursday, primarily to complain about TPM’s characterization of his contributions to the op-ed. In particular, he objected to TPM’s observation that passages from the op-ed bore similarities to Manafort’s public defenses of himself, especially cooperation with NATO and a deal to begin denuclearizing Ukraine.

“I’ve read your piece about this story,” he wrote. “And was unpleasantly surprised to see very strange allegations that if I stipulate in my op-ed certain ideas and facts that were in this or that way earlier claimed by Manafort it allegedly looks suspicious.” Enumerating Manafort’s accomplishments, Voloshyn said they were “just factual,” which explained the similarities between his op-ed and Manafort’s public statements. “[T]here is no wonder that Paul when asked of his work in Ukraine and me writing about the same topic stress on same things.”

But on Friday evening, prosecutors filed copies of the op-ed, both its final form—as first published by TPM on Wednesday—and, crucially, in a tracked-changes version, showing the parts of the text Manafort is said to have asked to have altered himself. They do indeed reflect the points Manafort has made in defense of his lobbying in Ukraine in the past:

“HERE NEED TO ADD a couple of major reforms that [Viktor Yanukovych] brought to country in order to position Ukraine to apply for membership,” Manafort apparently wrote. “Reforms that changed a Soviet based legal economic framework to a western one. (increase of NATO exercises/ Nuclear deal/)”

The version submitted by Voloshyn contained a new paragraph praising the Yanukovych, the Putin-friendly strongman Manafort helped bring to power, for his administration’s participation in NATO and the nuclear deal and crediting them to Paul Manafort, helpfully outlined in red in a separate document by prosecutors.

Voloshyn also shared exclusively with TPM emails dated Dec. 1 and Dec. 4 from Kilimnik, who has been described as Manafort’s “man in Kiev.” Kilimnik, who did not return a request for comment, is “assessed to have ties to a Russian intelligence service” according to prosecutors, an allegation he has denied to other news outlets.

Voloshyn strongly denied lending his byline to Manafort. “I didn’t correspond with Manafort directly at all,” he told TPM, a claim first reported by Bloomberg. “Just with Kilimnik. And it was his own initiative to forward it to Paul for review. But I hadn’t heard from him any feedback but for only phrase from Kilimnik [that] ‘Paul asked to pass you his deep gratitude for your honest position and friendly support’. No editions were intriduced [sic] by Paul.”

In the emails provided by Voloshyn, Kilimnik writes in Russian (translation by Alan Yuhas for TPM) on Dec. 1:

Take the draft with my small corrections. I caught some kind of flu, so I don’t particularly think there’s anything to add there – there’s one paragraph detailed in yellow, maybe you’ll remember what happened there. And if you finish writing, toss me plz the final version, just in case. But in general the article’s [brilliant]. :)) I like it a lot. And the most important truth is that the truth always prevails.”

Kilimnik replied again to Voloshyn on Dec. 4, the day the Mueller probe said Manafort’s participation in the project had violated his bail.

I fixed up a couple commas… Now I’ll toss it to Paul so he can quickly glance from the perspective of legal questions that are worrying him, and immediately swing back around Huge thanks

The next email, the same day, reads:

Paul looked it over, he’s very grateful. So let’s get it up

The latest filing Friday by prosecutors was a response to Manafort’s defense of the op-ed, which was obtained by TPM this week after they first raised concerns that Manafort was involved in its drafting. Prosecutors had initially sought to file the op-ed draft and its arguments about it under seal, but in the filing Friday said that was seeking to file those documents publicly because the op-ed was eventually published at the Ukrainian outlet it was intended for. According to prosecutors, Manafort’s attorneys “assured the government that the op-ed piece would not run.”

The editor of the Kyiv Post told Bloomberg he never intended to run the article. Kilimnik did not immediately return a request for comment. Manafort’s spokesman declined to comment.

Read the full court filing by prosecutors: