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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November 2015 could heading for the record books as the warmest on record in East Anglia.
Showers will largely die away this evening and winds will decrease. Feeling chilly with clear spells. Lows of 3 deg C.
This afternoon will see squally showers- these will be occasionally heavy. Becoming very windy later with gales.