I would think sporting arenas are an obvious target. And as for security; in the recent Charlton v Burnley match, at least a dozen flares were tossed on to the field of play by Charlton fans, interrupting the match, as part of some demonstration against the board. If they can smuggle flares into our grounds, then believe me, they can smuggle component parts of explosive devices in for someone to construct in situ.
Ken, that's what I was thinking. There's loads of Islamic players in the Premier League, it would be dead easy for them to smuggle in bombs or weapons.
A supprters club in Iraq (I think) has just been the scene of a massacre. Apparently football is 'un-Islamic'. Now, I hate, loathe, detest football (you get the idea) but I'd never considered blowing up the spectators. Yes, it's a sensible target from their point of view - as are pop concerts etc...
I would imagine that the security company involved will have to fork out for the policing of the re-scheduled match plus, quite possibly, other expenses incurred by both teams and their supporters.