A dirty tricks row has broken out between two leading political magazines over how one of them came into possession of a recording of the other’s interview with a government adviser who was later sacked.

The New Statesman is investigating how the Spectator, its arch-rival, obtained the recording of its interview with Roger Scruton. Scruton was removed from his job advising the government on housebuilding standards within hours of the New Statesman’s article based on the interview appearing online this month.

The piece included quotes from Scruton that appeared to show him repeating antisemitic statements and suggesting Islamophobia was a “propaganda word”. Scruton has accused the leftwing magazine of misquoting him and stoking a Twitter witch-hunt.

The issue turned into a cause celebre for conservatives, who insisted quotes in the New Statesman piece – such as “Each Chinese person is a kind of replica of the next one and that is a very frightening thing” – were part of a longer discussion by Scruton about the power of the Chinese state to impose its will on citizens, rather than racism. Several Tory MPs who initially condemned the comments later retracted their statements.

The New Statesman deputy editor, George Eaton, who wrote the article, later exacerbated the situation by posting a picture on Instagram of himself posing with a bottle of a champagne, captioned: “The feeling when you get rightwing racist and homophobe Roger Scruton sacked as a Tory government adviser.” He later apologised for the post but said he stood by the content of the interview and how it had been written.

This week’s cover story in the rightwing Spectator, headlined “Anatomy of a modern hit job”, quotes at length from a full recording of the interview obtained by the story’s author, Douglas Murray, prompting serious concerns at the New Statesman office over how its rival obtained the tape.

The only known recording of the interview was made on a dictaphone in the possession of Eaton, who later uploaded the file to his computer and forwarded it to the publication’s lawyer. Scruton is not thought to have made his own recording of the conversation.

Murray did not respond to a request for comment. He had spent weeks urging Eaton and the New Statesman editor, Jason Cowley, to share the recording using the hashtag #ReleaseTheTape. On Wednesday night, he tweeted: “To all those people wondering why I stopped asking @georgeeaton to #ReleaseTheTape. It’s because I got the tape …”

The Spectator editor, Fraser Nelson, said he would not be revealing his magazine’s sources and said he could not remember a similar situation where an interview tape had been leaked.

“I would never have put this in the magazine if it was just a case of ‘journalist exaggerates interview,’” Nelson said. He said his concern was about the government’s decision to sack an adviser on the basis of an interview and only ask questions later.

“This isn’t about George Eaton or the New Statesman, it’s about Twitterstorms,” Nelson added. “I genuinely like and admire the New Statesman, Jason Cowley does a good job, and it gives me no pleasure to run a story that puts them in this position.”

Scruton, who has been criticised in the past for comments on homosexuality and Islamophobia, did not respond to a request for comment. He has previously said he gave the interview to the New Statesman “on the assumption that as the magazine’s former wine critic, I would be treated with respect”.