it wasn't a top secret. everyone involves those professional "movement" know that. actually i am kind surprised that china didn't know that.
they had quite a few activities since last year and posted video clips on youtube. those were the signs for the coming troubles and no one in china noticed that? gees, someone ought to be fired or reprimanded for this.
here is what i read 北京武警決勝奧運大練兵應對破壞分子, what hell they are thinking? most of troubles would be demonstrations some sort from those anti-china groups. what are you going to do with those 武警?