DOZENS of dead fish have been found in the River Irwell following a diesel spill from a Haslingden supermarket.
Thousands of litres of fuel leaked into Langwood Brook from a Tesco petrol pump last Thursday morning.
Tesco said the problem had been solved and there was no danger to the public.
But anglers have reported seeing large trout dead on the riverside between Rawtenstall and Radcliffe and called the spill ‘very upsetting’.
Michael Duddy, chairman of the Salford Friendly Anglers Society, said: “It must have been bad because fish are quite clever, and if they notice the water quality change they will swim down a side stream.
“If the Environment Agency hadn’t reacted as fast as they had, it could have been total environmental devastation.
“It’s very upsetting seeing this happen to the river because it was basically an open sewer for 30 years and this could just reinforce that it is okay to just throw your rubbish in there.
“We are realistic, we don’t want a perfect river we just want what everyone has else has got which is somewhere clean.
“We want to know what went on for this to happen.”
Environment Agency officers are carrying out an investigation, collecting evidence and investigating reports of dead fish.
A Tesco spokesman said: “We stopped the leak on Thursday morning and the fire service have advised us that there is no immediate danger to the public.
"The Environment Agency are now working with our engineers and other partner agencies to ensure the ground is cleaned up.
"Our store colleagues have been in touch with local residents to apologise for any smells caused by the leak and are keeping them closely updated as the clean-up progresses.”
An Environment Agency spokesman said: “Environment Agency officers have been on site in Haslingden near Rossendale following a petrol spill. We are providing advice on how to minimise the risk to the environment.”