Investigators probing death of tens of thousands of fish in River Nene appeal for public's help
The Environment Agency is appealing for the public's help after an estimated 100,000 fish were found dead in a river.
It is suspected the animals died after an unknown substance contaminated the River Nene at Ferry Meadows in Peterborough.
The Environment Agency is urging anyone who saw any suspicious activity by the river on Sunday pr Monday, 10 or 11 December, to get in touch.
As a huge clean-up operation continues, people are also being asked to keep away from the water.
"It is very upsetting and we are absolutely determined to get to the root cause of the disaster," Rob Harris, chairman of the Peterborough and District Angling Club told ITV News Anglia.
"Pollution is a big thing and we are determined to get to the bottom of it and to find out who's responsible and to make them pay.
"This is not a natural occurrence, whether accidental or intentional. And if it was accidental, there should be mitigation really - there should be steps in place to stop that happening."
Mr Harris said the site had previously been polluted around a decade ago.
"It has taken a very long time to recover from that," he said.
"It is only this year, a decade later, that we've been looking at the site and checking it to see if it had recovered from this.
"We are going to struggle to maintain fish stocks now as they are already under a lot of pressure from other factors. The last thing we need is a pollution incident, a man-made incident."
There were fears the scale of the contamination could affect other wildlife but so far that has proved unfounded.
"There are a lot of birds, mammals and dog walkers in the area," said Mr Harris.
"There doesn't appear to be any impact at the moment on other wildlife which is a massive positive."
Anyone with information should contact the Environment Agency incident hotline on 0800 80 70 60.
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