Hundreds of fish dead in River Nene near Peterborough
Hundreds of fish have died in a Cambridgeshire river, potentially due to the hot weather.
Low oxygen levels in the River Nene at Whittlesey have been blamed for the death of 300 baby roach, a spokesman said.
The death of 350 baby roach near Stanground is unexplained, he added, as oxygen levels were normal and no pollution was present.
The River Cam is also being monitored after reports of fish "gasping".
An Environment Agency spokesman said the heat was one factor in oxygen levels dipping in rivers.
The Environment Agency has asked members of the public to contact them if they see evidence of "fish in distress".