New York Post op-ed editor Seth Mandel ripped Brian Stelter on Sunday, blasting the CNN anchor over his interview with New York City Mayor — and frequent Post critic — Bill de Blasio.

Mandel accused Stelter of allowing de Blasio to attack his paper and the broader Rupert Murdoch empire without offering sufficient pushback.

“Are you doing a parody of yourself? You brought him on and let him smear all the work we do and you didn’t f—ing challenge him on ANY of it,” said Mandel. “You ridiculous soulless clown.”

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Is that a joke? “Post staffers say it makes me feel unsafe”?? Are you doing a parody of yourself? You brought him on and let him smear all the work we do and you didn’t fucking challenge him on ANY of it. That’s how you feel about local news, Brian? You ridiculous soulless clown.

– Seth Mandel (@SethAMandel) August 13, 2018

Stelter was caught by surprise by Mandel’s criticism and attempted to take the high road.

“Your rage is shocking and unbecoming of you,” said Stelter. “I can see that you don’t want to have a real conversation. Have a good night, hope you have a better tomorrow.”

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Your rage is shocking and unbecoming of you. I can see that you don’t want to have a real conversation. Have a good night, hope you have a better tomorrow.

– Brian Stelter (@brianstelter) August 13, 2018

But that was just the beginning.

“You gave [de Blasio] an unchallenged platform,” Mandel charged. “All because you want to keep the heat on Fox–and the NY Post be damned. I hope it was worth it.”

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You gave him an unchallenged platform. All because you want to keep the heat on Fox–and the NY Post be damned. I hope it was worth it.

– Seth Mandel (@SethAMandel) August 13, 2018

“I don’t know what interview you watched. I challenged him over and over again,” Stelter snapped back. “BTW: I would never call anyone a “ridiculous soulless clown,” and I’m astonished that you did.”

I don’t know what interview you watched. I challenged him over and over again. Again, here it is: https://t.co/6DleOhNIAo BTW: I would never call anyone a “ridiculous soulless clown,” and I’m astonished that you did.

– Brian Stelter (@brianstelter) August 13, 2018

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The spat was over de Blasio, who has increasingly fashioned himself as a media critic. A review of the video does show that the CNN reporter did challenge many of de Blasio’s claims.

“When it comes to Newscorp they have a political mission and we have to be able to talk about it,” said the mayor in once instance.

“But singling out Newscorp. It’s like Trump singling out CNN. Two wrongs don’t make a right,” Stelter hit back.

You can watch the full interview from CNN here.