There was a lot of construction going at the airport, I wouldn't be surprised if they loaded the scrap on of the construction trucks and whisked it out of the airport.
However it happened mate its not clever when so much investment has gone into security. Lot of kilos.
Some sh*t stole a metal drain cover from the front of our building last week and we are viewing cctv cameras at the moment and we are sure we will catch the culprit. To steel 3000kg must have been hard!