Prof John Ashton, a public health expert based in Cumbria, has warned of the dangers of drinking super-chilled cocktails after a Lancashire teen had to have part of her stomach removed after drinking a cocktail made with liquid nitrogen.
Prof Ashton told ITV Granada: "It's extremely dangerous. You've got alcohol, which in itself is dangerous, we've got liquid nitrogen which is a dangerous chemical.
"People should not be fooling around with these sorts of things."
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Five people were killed and dozens more were injured after a car and knife attack in the capital on Wednesday afternoon.
Among those expected to attend the ceremony will be former US President Bill Clinton and ex-Northern Ireland first minister Peter Robinson.
Five people have been killed and 40 injured after a car and knife attack in London on Wednesday.