Fish death probe launched into River Teifi pollution
All the salmon and sea trout in a two-mile stretch of the River Teifi in Ceredigion have been killed by pollution, Natural Resources Wales has confirmed.
More than 1,000 fish died as a result of what is believed to have been a slurry leak in the Tregaron area.
NRW said the majority of fish up to six miles (9.6km) downriver had also died.
The environment body said an investigation was ongoing and enforcement action could follow.
NRW teams have been working to ensure control measures are in place to prevent further pollution, and staff are carrying out surveys to assess the impact on other river life.
Gavin Bown, south west duty manager for NRW, said the Teifi was one of the most important recreational and net fisheries for salmon and sea trout in Wales and was vital to the tourism industry.
"The fisheries of Wales are iconic and highly valued so it's devastating when pollution incidents happen," he said.
"We'll work with our partners and do all we can to restore the river as quickly as possible."
Councillor Rhodri Evans, Ceredigion council's cabinet member for lifestyle services, said there were concerns among anglers about the impact of the pollution.
But he added he was hopeful the measures put in place to prevent further contamination would be successful.
Conservationist and presenter Iolo Williams described it as "an environmental disaster" and said it would take decades for the river to recover.