A river in north Wales which was hit by a major pollution incident this summer has been restocked with thousands of fish.

A hundred thousand fish were killed in the incident on the River Dee last July.

On Tuesday, the Environment Agency released around twenty thousand course fish into the lower stretches of the Dee near Aldford Brook.

The river is one of the most regulated and controlled rivers in Britain.

It is important - not just for its beauty or fishing - but as a source of drinking water for nearly three million people.

Investigators

But three months after the incident the Environment Agency is no nearer to finding the cause of the devastating fish kill.

Theories include industrial pollution or even deliberate poisoning but investigators failed to find evidence of either.

Scientists still are not sure what was responsible although it is possible the fish died from lack oxygen when a plug of deoxygenated mud was stirred up by heavy rain.

The agencies handling of the investigation has been heavily criticised by local anglers.

On Tuesday, the agency set out to rectify the shortage of fish by releasing 20,000 juvenile roach into Aldford Brook.

Other fish including chubb and barbel will follow in the next few months.

It is anticipated the river will be getting back to normal by the time the results of an internal inquiry on the agency investigation are released later this year.