I've uploaded some more definitive proof.
Picture (you can see the cannon on the top left)
http://s1036.photobucket.com/albums/...n.jpg&newest=1
Video (cannon can be heard and flash can be seen at the top of the screen around the :10 - :11 second mark).
http://www.youtube.com/watch?v=LfiKRD0eWtU
I posted this over at OperationSports already, but I decided I'd join here too.