A police spokeswoman said the boy's death was not being treated as suspicious but it was not clear if he fell into the water or went in deliberately before getting into difficulty.
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It's going to be a cloudy afternoon with the chance of the odd shower. Feeling cold. Highs of 6 degrees C.
An investigation is underway after a horse and pony sanctuary burnt down in Norwich.
It will be a generally cloudy day. Some bright or sunny spells are possible during the morning.