Justin Bieber has become a hugely divisive figure.
A number of high profile events last year saw the Canadian singer gain huge criticism, while his army of followers remained steadfastly at his side.
Last year the Black Keys spoke to TMZ, with drummer Patrick Carney reported as saying: "Grammys are for music, not for the money, and he's making a lot of money. He should be happy."
In response, Justin Bieber tweeted: "The Black Keys drummer should be slapped around haha".
Cue all manner of social media based threats coming the way of Mr Carney. Reflecting on this to Rolling Stone, the drummer is quite clearly still stung by the singer's move.
"Justin Bieber, like a fucking irresponsible asshole, sicced 40 million Twitter followers on me because I paid him a compliment he didn't understand. I'm saying that he should be grateful that he has a fucking career in music. And he shouldn't be fucking telling his followers to slap me, and then also be doing anti-bullying bullshit. It's so irresponsible."
Continuing, Patrick Carney said simply: "I mean, Justin Bieber is a fucking moron".
But wait! He isn't going to stop there. "Honestly, I feel bad for him. Every single person who works with him should fucking be embarrassed that they don't. . . No one is doing him any favors, you know? And honestly, I don't dislike his music. I don't listen to his music, but he needs to not conduct himself that way."
The Black Keys' new album 'Turn Blue' is out now - check out the Clash review HERE.