I must admit I hadn’t heard much about this guy but I’m not a great “Anonymous” fan, I think it’s too threatening, too counter-productive, perhaps he was just flashing off skills he’d learnt inside. Can’t thank him for the Kill Cops banner no matter which side he is on! Might not be him but the profile fits and he has been living here.
https://www.wired.com/2016/12/anonymous-barrett-brown-free-ready-pick-new-fights/