Environment Agency staff have spent the day dealing with an emergency at a canal in Grantham after hundreds of dead fish were discovered this morning.
It's thought they died through lack of oxygen caused by the hot weather.
Chemicals have now been added to the water to bring the oxygen levels back to normal.
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Cold and windy with further scattered sleet and snow showers overnight, most of these falling in the north and west.
A cold and blustery night with rain, sleet and snow showers. These will be most frequent in the northwest with snow accumulations possible.
Schools "should be promoting British values" to tackle extremism, the Education Secretary Nicky Morgan has said.