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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The region has enjoyed its warmest day of the year and the hottest February day for five years.
A campaign has been launched to attract more American tourists to East Anglia by highlighting the region's links to the US military.
More than 13,000 primary school spaces are needed in Essex in the next two years.