@Dan_Danielson1 was at RAW tonight and passed on the following regarding CM Punk's altercation with a fan.
Dan said the fan pushed at CM Punk in the back of the head. It was after this that CM Punk hit him with a spinning back fist and continued to go after him.
There have been some questions as to whether CM Punk went after the wrong fan, but many of the videos surfacing online don't show any action taken by the gentlemen other than putting his glasses on before CM Punk swung at him. Dan confirms the man who got hit by CM Punk was the man who pushed CM Punk from behind.
We'll continue to follow this story as it develops.