President Donald Trump has lashed out in an erratic Twitter tirade a day before the first charges are expected to be filed in the investigation into Russian interference in the 2016 election.
The US leader accused Hillary Clinton and the Democratic Party of using the investigation as a "witch hunt for evil politics".
He also said on Sunday that the conversation about Russia was a distraction to prevent Republicans from passing tax reform.
Trump's rant comes after Robert Mueller, the special counsel heading the wide-ranging probe into whether there was collusion between Russia and members of Mr Trump's presidential campaign, empaneled a grand jury in the case.
CNN has reported, and other media have confirmed, that the grand jury has brought its first charges stemming from Mr Mueller's probe.
It is not known who was charged or what they were charged with, but CNN said details could be made public as early as Monday.
Mr Trump has repeatedly denied any collusion between Russia and members of his White House campaign, and denounced the probe as a "political witch hunt".
The most important role of a grand jury is to determine whether the evidence presented merits bringing charges.
If so, an indictment is produced and a case may go to trial. Even before that, though, grand juries have the power to issue subpoenas compelling witnesses to testify or for documents to be produced.
Grand juries do not determine guilt or innocence. Rather, they decide whether probable cause exists that a potential crime has been committed and if charges should be brought.
They typically meet in the strictest secrecy and deliberations are confidential.
The grand jury gets its name from the fact that it is often made up of between 16 and 23 US citizens, rather than the usual six or 12 for a jury trial.
Former US President Richard Nixon appeared before a grand jury for two days in 1975 - nearly a year after resigning the presidency - in connection with the Watergate scandal.
In August 1998, Bill Clinton became the first sitting US president to testify before a grand jury as he was being investigated for alleged perjury and obstruction of justice.
Former Trump adviser Roger Stone has been suspended from Twitter following a profanity-laced rant against US journalists.
The tirade, following reports on reports of charges in the Russia investigation, got more obscene as it went on.
"Breaking: Mueller indicts PaulManafort's driver for double parking," Mr Stone posted.
Later: "@donlemon stop lying about the Clinton's and Uranium you ignorant lying c***sucker !!!! You fake news you dumb piece of s**t."
He also called some CNN personalities "human excrement".
The right-wing firebrand's account has been suspended at least twice before, in March and April of this year.
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