A number of teenagers are reported to be suffering from sickness and diarrhoea after swimming in a make-shift pool filled with river water in Hebden Bridge.
The local high school, Calder High in Mytholmroyd, has written to parents saying a number of students had become ill after taking part in what was "not an officially organised activity".
It's understood that river water was somehow pumped into the hollowed out skate park in Calder Holmes - much to the delight of youngsters who took a dip to cool down. Environmental Health officers are advising anyone with concerns to contact their GP.
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A much better feel to the day on Monday
Much brighter than previous days this week. Decent sunny spells, large areas of cloud around North Sea areas
A few thunderstorms clipped Lincolnshire on Friday night, but they have now decayed and it should be mostly just cloudy on Saturday