Environment Agency Wales is investigating the impact of a pollution to the River Ebbw.
An industrial adhesive spill at a site on the Rassau Industrial Estate has caused a white slick roughly two kilometres long. The substance was spilt into the Rassau Brook and has since moved through the Nant Melyn to the River Ebbw.
Agency biologists are investigating the spill to see what impact it has had on aquatic life.
Ashley Lansdown of Environment Agency Wales said: “We are very grateful to the member of the public who reported this to us.
“Early reports help us to minimise the impact of pollution on the environment. If you see any pollution, please call our Incident Hotline on 0800 80 70 60.”