Its really confusing now. The plane wouldn't have been rolling down the runway without the clearance from the ATC. I would assume that the ATC were aware of the fire exercises being conducted on the runway. Did the ATC ensure that the runway was clear by asking the fire guys to move out before giving the A320 the thumbs up? Did the fire guys break the ATC's instruction to not cross the active runway? Obviously, it would be wrong for me to point the fingers at the ATC/Fire guys/A320 before listening to the recordings. That will make everything clear.