This is a good reminder. When I got to the South Stand Atrium, before the game, there were two young, tall, skinny black guys wearing red stuff and asking a steward for directions - then they disappered into the crowd. I thought to myself, 'surely not', but I swear they were goons. Looked like they were probably vloggers, out to create any upset they could.
It kicked off with two Woolwich fans in the south stand so I suspect it was them.