Planted bomb makes more sense.
Just on radio news; now they are saying that it was one large explosion; your theory is starting to make a lot of sense.
If it came in from outside it must have been more than a mortar round or RPG. I don't think the Sunni Jihaddis have any heavy artillery, but who knows?
My money at this point would be that it was an inside job - IED in a garbage can most likely.
Keep us posted, if anybody has a clue.
It would seem so...this was an inside job and my heart grieves for the heroes. A couple seconds later I am really p***ed off!