Personally I think the airport authorities acted correctly in closing the airport. If most units had been called out to two suspect fires, they had no option but to stop all aircraft movements.
because having 60-80 firemen and 12 firetrucks standing around twiddling their thumbs, where the fire had been extinguished (probably by the first truck on the scene) and the aircraft was in a remote parking area, had no one onboard for the last 8 hours, is a good use of firemen and an extremely busy airport.