Longtime Donald Trump adviser and ally Roger Stone spoke at the conspiracy-fueled “Lee Harvey Oswald Conference 2016” this weekend, telling attendees that former President Lyndon Johnson was behind the assassination of President John F. Kennedy and promising that a President Trump would put the entire Clinton family in prison.

The conference, which had the theme of “Oswald: The Patsy,” was executive produced by Kris Millegan, whose publishing company Trine Day specializes in conspiracy theory books with titles like The 9/11 Mystery Plane: And the Vanishing of America, which posits that the 2001 terror attacks were carried out by the U.S. government. The event was co-produced by Lorien Fenton, who also organizes conferences on UFOs and “secret space programs.”

Stone described the Oswald conference as “furthering the scholarship on the question of who killed John F. Kennedy and why.” (Stone has published a book alleging that Lyndon Johnson was behind JFK’s assassination. He has also claimed to be working on a book about the Clintons secretly murdering JFK Jr.)

In his presentation on October 16, Stone devoted a large chunk of his remarks to touting Trump’s candidacy to the audience, describing the campaign as “an insurrection” and “an uprising” against the “ruling elite.” He added, “This is D-Day for the ruling elite. They know, among other things -- and I think Trump made this very clear in the last debate -- if he’s elected, Bill and Hillary and their crooked, nasty, foul-mouthed little daughter, they’re going to prison.” (Stone and fellow conspiracy theorist Alex Jones have led the charge on calling for Hillary Clinton to be sent to prison, which Trump has recently adopted as a talking point.)

During his remarks, Stone revisited his warning that America is “headed into a nuclear war with the Russians.” He also later alleged that President Obama is “prepared to have a war, if that's what it takes to elect this gravely ill woman to succeed him.” He also re-upped his bizarre allegation that Bill Clinton is not really Chelsea Clinton’s father.

Stone has long been an active conspiracy theorist (though during his remarks, Stone dismissed being labeled a “conspiracy theorist,” saying instead he is a “conspiracyologist” and a “conspiracy realist” ). His book Jeb and the Bush Crime Family argues that President George H.W. Bush was involved in the attempted assassination of President Ronald Reagan in 1981. Stone also claims that Hillary Clinton aide Huma Abedin was connected to the 9/11 attacks, that the Clintons have had numerous people murdered (including four people during the summer of 2016 alone), and that the collapse of World Trade Center Building 7 was “suspicious,” along with numerous other fringe and disproven theories.

Throughout the 2016 election cycle, Stone has allied himself with and become a regular guest on the radio program of Alex Jones, the self-described “founding father” of the 9/11 conspiracy theory movement.

During the campaign, Stone has been in regular contact with Trump, who has increasingly pushed conspiracies peddled by Stone in recent weeks, including the outlandish claim that the election is “rigged” against the Republican nominee.