Michael Flynn, the retired general and former Trump national security adviser, has endorsed a right-wing call for the president to suspend the U.S. Constitution, declare martial law and hold a new election supervised by the military.

In a Twitter post on Tuesday night, Flynn re-tweeted a call by an Ohio-based group called We The People Convention (WTPC) for dumping the results of the Nov. 3 presidential election that Trump clearly lost and holding another one.

Flynn, who twice pleaded guilty to lying to the FBI during the bureau’s investigation of Russian meddling in the 2016 election, received a full pardon from Trump just last week.

WTPC ran a full-page advertisement in the conservative Washington Times on Tuesday, claiming without evidence that the U.S. is faces a threat by “the socialist/communist left” that is more serious than any in the nation’s history — even the Civil War.

The ad — really a far-right manifesto — calls on Trump “to immediately declare a limited form of Martial Law and temporarily suspend the Constitution and civilian control of these federal elections for the sole purpose of having the military oversee a national re-vote.”

In a press release, WTPC’s president, Tom Zawistowski, claimed that “massive, planned, illegal election fraud conducted by corrupt Democrat/Socialist Party operatives across our nation to steal our vote,” Newsweek reports.

“There’s a lot more awful stuff in the declaration,” writes Josh Marshall of Talking Points Memo. “But that quote, I think, includes all we ever need to hear: declare martial law, throw out the results of an election you lost. In a democracy, this is essentially sedition, a call to overthrow the state.

Flynn’s re-tweet of a link to the ad amounts to an endorsement of that view.

Newsweek says WTPC “provided no evidence to support its claims, which have been debunked by bipartisan election officials and Trump’s own Justice Department,” including Attorney General Bill Barr.

Trump claims his election loss was the result of a complex fraud.

“QAnon followers, online extremists and fringe groups like WTPC have proved fertile ground for the baseless claims of electoral fraud,” Newsweek says, “helping create an alternative narrative in conservative media and on social media that experts have warned could encourage real-life violence.”