I wonder if he was trying to grab the i-phone and came away with the mic instead.
I watched it a few times, and from what it sounds like, some guy in line got pissed off about the crew trying to keep him back. You can hear him say something about "...f***ing phone."
As he walks up behind the reporter, you can clearly hear him say (as he's grabbing), "Gimmie that f***ing mic. Don't f***ing mess with me!"