…return to the bar with a chainsaw and look for some revenge.
That is exactly was Dinnen did and it was all captured on the security cams inside and out of the bar. While he was looking for a specific person (who actually had already left the bar) Dinnen went on a rampage threatening some with the chainsaw, and actually got one person trying to defend himself with a barstool. That patron, Adrian Pryor, suffered a torn tendon when he attempted to assist a friend.
With other patrons diving, scrambling and fleeing to get out of the way, Dinnen cut through a fire door, made a mess of the place and eventually was stopped with a collection of pool cues, chairs, stools and lots of people kicking him.
He was arrested and charged with grievous bodily harm and something the english call, “affray”, because he threatened people that caused them to fear for their safety.