Was it that long ago Paul, doesn't time fly when in lockdown
If I remember correctly the problem led to a bit of a stand off by the vessel's which went to fight the fire and if they should put anybody onboard as there was some difficulty getting hold of the cargo manifest, in those days and indeed in today's world what was on the manifest does not always equate to what some of the wagons were actually carrying.
A similiar event took place many years ago when a small commercial aircraft took off from Teesside Airport carrying two passengers and of course the Pilot along with a "Third party" only to belly flop in a field just beyond the Airfield, the Fire Brigade went to assist only to be met with a stand back instruction as the " Third party" was Radioactive material which of course they were not aware of. Can't remember if I.C.I. were fined for non declaration of hazardous cargo or not.