I can't help but notice that the airline professionals here are quick to respond with what they believe are acceptable reasons/excuses. Sorry folks, keeping passengers (i.e. customers) virtual prisoners for 9 hours when they have effectively arrived at their destination city is simply not acceptable at all, whoever or whatever may be responsible. It is perfectly valid for those involved to complain and for the entire episode to be thoroughly investigated. I also believe that all pax should be handsomely compensated!