Officers are on site trying to trace the source of the pollution and are currently assessing the environmental impact of the pollution on the water quality and fish populations.
A spokesperson from Environment Agency Wales said:
“The river is currently appearing a dull grey colour due to suspended solids in the water.
So far, we haven’t noticed any signs of fish in distress but we will continue to monitor the situation closely until we identify the source.
We’d like to thank local people who have reported this to us, and would urge anyone who has any information about this incident to report it to us on our incident hotline on 0800 80 70 60”
