The 'detainee' was identified as Chris Manfredonia, whose 6-year-old daughter attends the school, and he was heading there Friday morning to help make gingerbread houses with first-graders. He apparently ran around the school after hearing the shots, trying to find his daughter and ran into the police, who briefly detained him.
The video 'proof' Mikey posted is proof of nothing. It was some of the first video coming out during the incident and a LOT of the first bits of information were later fact checked and a lot of it proven to be totally wrong or complete hooey.
But hey, I've got this foolproof theory that Don Cherry and Rita MacNeil are the same person - maybe Mikey would like to run with that too.