The special counsel investigating Donald Trump's efforts to overturn his election loss has turned his attention to a White House meeting where the former president and a pair of notorious conspiracy theorists discussed a plan to seize voting machines, sources told CNN.

Federal prosecutor Jack Smith was last November appointed as special counsel to lead the Department of Justice's investigations into two separate, potentially criminal matters, one concerning Trump's handling of classified documents and the other his efforts to cling to power following the 2020 election.

Of particular interest to Smith is a December 18, 2020 meeting at the White House where Trump was joined by attorney Sidney Powell, who was falsely claiming that electronic voting machines were hacked by foreign adversaries, sources told CNN. Powell was sanctioned last year for filing a string of frivolous lawsuits claiming election fraud.

Powell was joined at the meeting by Mike Flynn, a retired three-star general who has falsely claimed COVID-19 was created to help Democrats steal the 2020 election. Trump had pardoned Flynn — his first national security adviser, convicted of lying to the FBI about his contact with a Russian diplomat — less than two weeks earlier.

Flynn, prior to the meeting, had for weeks been pushing the idea of seizing voting machines, arguing that Trump could unilaterally demand it be done. "He could immediately, on his order, seize every single one of these machines," he told right-wing media outlet Newsmax the day before the White House meeting, arguing that Trump could declare martial law and order a re-do of the 2020 election.

The December 18 meeting devolved into a shouting match between Trump's allies and White House lawyers, according to reports, with the latter informing the former president that the proposal would not be legal.

They were not the only ones counseling the former president that voting-machine scheme was unwise.

According to CNN, citing sources familiar with Smith's investigation, two former Trump officials, widely seen as staunch conservatives and loyal allies of the ex-president, were asked about the plan during their appearances before a grand jury. Ken Cuccinelli, who in 2020 was serving as the acting deputy secretary of the Department of Homeland Security, is said to have testified that he "made clear at all times" that DHS lacked the authority to seizing voting machines.

Appearing earlier before investigators with the House January 6 select committee, Cuccinelli had said he was contacted by Rudy Giuliani — Trump's personal attorney and another participant in the December 2020 meeting — and asked if DHS had the authority to pursue the Powell-Flynn plan. "And I told him: We don't have any authority to grab these machines," Cuccinelli said, according to a transcript of his deposition.

Chad Wolf, who served as acting secretary of the Department of Homeland Security, was also asked about the plan, per CNN. Robert O'Brien, Trump's national security adviser from 2019 to 2021, has also been asked about the scheme and his participation in the Powell-Flynn meeting, which he participated in via phone. O'Brien told prosecutors that he "had made clear there was no evidence of foreign interference affecting voting machines," according to the outlet.

Indeed, days after the 2020 election, the nation's top election security officials issued a statement via the federal Cybersecurity & Infrastructure Security Agency attesting that there was "no evidence that any voting system deleted or lost votes, changed votes, or was in any way compromised."

Trump, meanwhile, has responded to the investigation of his post-election actions with a string of personal attacks. In a speech on Tuesday following his arraignment in New York on felony charges of falsifying business records, he described Smith as a "lunatic" and bizarrely claimed that the special counsel had changed his legal name.