30 Rock star and comedian Tracy Morgan has been accused of an extreme anti-gay tirade onstage.

An audience member at a recent Nashville show claimed the bawdy comic said he would kill his son if he turned out to be gay and that homosexuality is a “mistake”.

Kevin Rogers wrote on Facebook that Morgan was “truly filled with some hate” towards gay people and did not appear to be joking.

He wrote: “I figured at some point the gay jokes would fly and I’m well prepared for a good ribbing of straight gay humour. I have very thick skin when it comes to humor; I can dish and I can take.

“What I can’t take is when Mr Morgan took it upon himself to mention about how he feels all this gay shit was crazy and that women are a gift from God and that ‘Born this Way’ is bullshit, gay is a choice, and the reason he knows this is exactly because ‘God don’t make no mistakes’ (referring to God not making someone gay cause that would be a mistake).”

“He said that there is no way a woman could love and have sexual desire for another woman, that’s just a woman pretending because she hates a f**king man. He took time to visit the bullshit of this bullying stuff and informed us that the gays needed to quit being pussies and not be whining about something as insignificant as bullying…

“He said if his son that [sic] was gay he better come home and talk to him like a man and not – he mimicked a gay, high pitched voice – or he would pull out a knife and stab that little N (one word I refuse to use) to death.”

Mr Rogers wrote that while some people walked out, others clapped and cheers as Morgan said gays should “take a f**king joke”.

He added: “The sad thing is that none of this rant was a joke. His entire demeanour changed during that portion of the night. He was truly filled with some hate towards us.”

Gay rights group Truth Wins Out has asked for an explanation but Morgan has not commented.

In 2009, some audience members walked of his gig in New York over risque jokes, which reportedly included calling homosexuality a choice.

30 Rock, created by Tina Fey, has won awards for gay inclusion.