Canadian DJ Deadmau5, aka Joel Zimmerman, has never been one afraid to speak his mind - but it seems that he's gone a step too far this time.

His fellow DJ Skrillex has responded to Deadmau5's inflammatory recent inflammatory comments - where he called a recent song produced by Skrillex 'shit' - and re-ignited a feud that stretches back between the one-time friends.

"I dont care bout ur personal career but the fact that u own ur own record label is sad.I feel sorry the artists you've signed," he tweeted. "youre great at finding talented people but ur leadership skills are atrocious. I'm sure you don't care tho."