This is not so. I quoted directly from the report, a publicly available document, which said that the scientists had previously regarded the possibility of a cataclysmic eruption as negligible but could not now rule it out.
Their actual words were:
The remote possibility of the present crisis generating a massively cataclysmic explosive eruption has never been absolutely precluded, but the received wisdom was that it had a negligible probability of occurring. However, the recent increase in explosive activity is such, and the uncertainties attending any hypothesis about the volcano's capacity to go cataclysmic are so great, that the potential hazard cannot be taken to be zero.
This is what I read over to the Press Association news agency, who reported it accurately. Dr Sparks is now suggesting I misquoted him. As you will see, I did not.
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