River Teifi pollution: 'Heartbreaking' to see dead fish
At least 1,000 fish have been killed following pollution of the River Teifi in Ceredigion, Natural Resources Wales has said.
Environmental officers said the water has been discoloured and believe the source was an agricultural site in the Tregaron area.
Salmon and sea trout are among the dead fish and NRW said the number was "rising".
Control measures have been put in place to stop the pollution spreading.
Fisherman Hywel Morgan described seeing the dead fish as "heartbreaking".