"It's inevitable that we will see some of this die-back disease in Cumbria. It's a problem that's been going on in Europe for a number of years now and now that it's in Britain it's going to spread relentlessly probably north and further west so I do expect we will see it at some point sooner or later in Cumbria and we'll have to deal with it when it comes here."
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The historic event always takes place on the last Friday in July.
Early enquiries suggest the men may have taken the drug Blue Valium. Two of them remain in hospital with breathing problems.
More than 8,000 people are expected to attend over the three day event, which starts at 7pm tonight.