TENS of thousands of fish were killed after a devastating pollutant flooded the River Irwell.
Now Environment Agency experts are working to trace the source of the pollution, which affected four kilometres of the river between Irwell Vale and Stubbins, Ramsbottom, on Thursday.
A member of the public alerted the Environment Agency officials after seeing dead fish in the river.
Officials found 36,000 dead fish including toneloach, bullheads, minnows, sticklebacks and brown trout, some up to 50 cm long and weighing 1.5kg.
A spokesman for the Environment Agency said: "Water samples have been taken and will be analysed to identify the pollutant.
"Agency officers are visiting a number of trade premises in the area in a bid to find where the pollution came from.
"The full effect of the danger to the river will not be known until further investigation has been completed."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article