Shocked nature-lovers woke up this morning to discover the River Crane poisoned, leaving many fish dead once again.

The Environment Agency was called following several reports that a section of the river at Twickenham had turned black and fish were in distress.

The source of the pollution has been traced to an outfall pipe upstream of the A30.

Environment Agency officers are currently at the scene working to minimise the impact of the incident.

Mark Heelis, of the Environment Agency, said: “This is a significant incident and it appears that many fish have been killed.

“Officers are working hard to minimise any further impact this incident has on the environment.

“A full investigation into the incident is under way and we will be providing regular updates on the incident as the situation progresses.”

The River Crane was polluted in October 2011 after a raw sewage spill killed thousands of fish.

David Waltham-Hier, who lives in Lincoln Avenue, said lots of small dead fish could be seen floating upside down on the surface.

He said: “So much work has gone into putting things right after the incident a few years ago.

“The river has been so clear but all that work has been ruined - people are down there in tears.

“My wife has been trying to keep the dogs away from it because the water absolutely stinks and looks a horrible murky grey.”

Another member of the public, who did not want to be named, said they were left with a sore throat and tingling lips and tongue after walking along the riverside this morning.

They added that the water smelled of chemicals.

To report any incident of pollution, call 0800 807060.