WASHINGTON – With major developments in the Russia investigation looming, President Donald Trump on Friday again launched rhetorical attacks on special counsel Robert Mueller and his prosecutors.

"A total witch hunt," Trump said during a series of early morning tweets.

As he has on previous occasions, Trump accused Mueller's team of political bias, he accused prosecutors of threatening witnesses and trying to get them to give false testimony, and he complained that Mueller has refused to investigate Democrats who allegedly had dealings with the Russians.

Trump's tweets came the same day Mueller and prosecutors are expected to file court documents related to two key witnesses in the Russia: former Trump campaign chairman Paul Manafort and former Trump lawyer Michael Cohen.

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The documents could offer insights into the state of the investigation into how Russia meddled in the 2016 presidential election by hacking Democrats and pushing fake news about Trump opponent Hillary Clinton.

Apparently believing the special counsel will soon file a report on his findings, Trump said at one point: "Will Robert Mueller’s big time conflicts of interest be listed at the top of his Republicans only Report."

In another tweet, Trump said his attorneys are preparing a counter-report to whatever Mueller produces.

"It has been incorrectly reported that Rudy Giuliani and others will not be doing a counter to the Mueller Report," he said. "That is Fake News. Already 87 pages done, but obviously cannot complete until we see the final Witch Hunt Report."

While Mueller has not commented on Trump's repeated attacks, legal analysts and critics say Trump is trying to intimidate prosecutors and rally his supporters in case he is formally accused of wrongdoing in the Russia investigation.

"Reading your tweets this morning tells me you're now pretty much every mentally ill homeless dude outside the bus station, screaming at the cops to publish your manifesto," tweeted Rick Wilson, author of Everything Trump Touches Dies: A Republican Strategist Gets Real About the Worst President Ever.

Also on Friday, former FBI director James Comey is scheduled to testify before the House Judiciary Committee and the House Committee on Oversight and Government Reform.

Trump's firing of Comey in 2017 is part of a Mueller investigation into whether he has sought to obstruct justice in the Russia investigation.

Trump repeatedly has denied collusion with Russia and obstruction of justice, and has described the investigation as a politically motivated attempt to reverse the election results of 2016.