Officials at the Environment Agency have blamed the recent heatwave for the deaths of thousands of freshwater fish, across the region.
The intense heat has caused oxygen levels in the water to plunge. There have been reports of fish in distress in Welney in Norfolk and Tiptree in Essex.
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Spring has arrived as the sun comes out and temperatures rise to 16ºC by Saturday
There'll be a lot of cloud at first this morning but the sun should break through in many places this afternoon.
The cloudy skies will remain tonight but at least temperatures will stay frost-free.