Wow, I am really looking forward to finding g out more about this. What agency were they with? How often do they do this? Was it random or targeted, and if the latter at the person or device?
Side note - he wasn't arrested, he was handcuffed, had a weapon stuck in his back, was detained, had an illegal search performed on his possessions, and all by purported law enforcement officers who refused to identify themselves. In many ways this is worse than being arrested - with an arrest there are other layers of law enforcement to appeal to and receive justice. With an arrest at least we would have officers names, charges, etc, which if faked could theoretically result in discipline or firing of the officer. I know it doesn't always work that way, but at least the checks and balances exist.
With this kind of officer-level illegal search and detainment, there is very very little that can be done to seek any sort of justice. If this kids mom wasn't a reporter, nobody would have heard or believed the story.