While conservative provocateur Milo Yiannopoulos insulted comics Lena Dunham, Leslie Jones, Amy Schumer and Sarah Silverman, his appearance on HBO's "Real Time with Bill Maher" was relatively tame — at least until the television cameras were turned off.

It was later, during an online-only "Overtime" segment of Maher's Friday night show, that two of Maher's three panelists hurled expletives at the Breitbart News senior editor.

Maher's booking of Yiannopoulos, author of the upcoming book "Dangerous," drew attention earlier this week when journalist Jeremy Scahill backed out of the show because of his "hateful diatribes." The conservative gadfly has become a lightning rod; his planned speech at the University of California, Berkeley, was cancelled earlier this month when protests erupted.

Maher, a free speech advocate, told Yiannopoulos that he thought he was "colossally wrong" on most issues, "but if I barred everyone from the show who I thought was colossally wrong, I would be talking to myself."

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Yiannopoulos called Maher his "favorite liberal" and directed most of his ire at female comedians.

"Your side has gone insane," he said. "The Democrats are the party of Lena Dunham. These people are hideous, mental people. The more the American people see of Lena Dunham, the fewer votes the Democratic Party is going to get."

Responded Maher about the "Girls" creator: "Let's not pick on fellow HBO stars."

The Breitbart editor said Schumer and Silverman "used to be funny before they contracted feminism." After the subject was brought up by Maher, he renewed hostilities with Jones that had begun with his review of the "Ghostbusters" film. Yiannopoulos' Twitter account was suspended last year after a series of racially insensitive tweets were directed at Jones, who is black.

On Maher's show, he called Jones "barely literate."

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Still, the interview segment featured few harsh exchanges with Maher, and Yiannopoulos was not included in a panel discussion that featured comedian Larry Wilmore, author and counterterrorism expert Malcolm Nance and U.S. Rep. Jack Kingston, a Georgia Republican. But online, Yiannopoulos joined the other three to answer questions from viewers.

That's when things got interesting.

The starting-off point was when Yiannopoulos defended his criticism of a transgender person and saying, without offering evidence, that transgender people were involved in a disproportionate number of sex crimes. Wilborn objected, saying that reminded him of the attitudes people directed at gays and blacks to demonize them in society. He noted that for a long time, homosexuality was considered a disorder.

"Maybe it is," said Yiannopoulos, who is gay.

"Maybe you are," Wilborn said, "But most homosexuals are not."

Nance observed that Yiannopoulos seemed confused about who and what he was. When Maher tried to referee, Yiannopoulos said that he always seemed to have "awful" people on the show, "who are so stupid."

That's when Wilmore exploded, telling Yiannopoulos to "go f--- yourself." Maher defended Nance, telling Yiannopoulos that "this guy has done things that allow you to" live.

When the oddity of an openly gay man being seen as a leader of the alt-right movement was pointed out, Yiannopoulos said that "the worst people on the far left and far right all hate me."

Retorted Wilmore: "I think you're leaving out a lot of people."

Nance added another expletive when the Breitbart editor said he had no problems with the issue of President Donald Trump and ties to Russian, profanely dismissing him because he was not an American. Yiannopoulos is British.

It stopped there. Kingston declined a chance to be the third panelist to swear at Yiannopoulos.