A COUNCILLOR has demanded action after a late-night pollution spill covered a 50-metre stretch of the River Calder in Whalley with white foam.

Pollution inspectors were called to the River Calder late on Thursday after a white frothy substance and numerous dead fish were spotted in a stretch of the river at Bridge End.

Coun Chris Sterry was called to the stricken river at 9.30pm by concerned residents who spotted the white foam floating towards Whalley Abbey.

He said: "I had just left a meeting and popped into the village pub, when someone rushed in and said I had better go and look at the river.

"Residents were out with plastic bottles collecting samples for about fifty metres and residents were out with plastic bottles collecting samples. A couple of them were close to tears and said they had spotted dead fish, but by then it was getting dark and I couldn't see the river under the foam.

"Whatever was in the water had clearly been whipped up by the weir upstream and this is a terrible shame, as wildlife on the river had been improving in recent years.

"I hope the authorities do all they can to find out the cause of the pollution and prevent it happening again."

A spokesman for the Environment Agency said inspectors were called out at 10pm and worked through the night to discover the source of the pollution.

But they returned to the scene during daylight hours after drawing a blank and were today still conducting investigations.

A spokesman said: "We still haven't determined the source of the substance and our officers will undertaking further investigations. We have cleared up the foam, but have been unable to find any dead fish. Our officers have taken samples, which will be brought to our laboratories for analysis.

"We have spotted fish swimming in the river, so the damage to wildlife does not seem to be as bad as first thought.

"We have so far not established the nature or source of the pollution, but will continue to monitor the situation."

Work on a £2million nine-month clean-up of the River Calder in Burnley was started in March by United Utilities, in a bid to stop untreated sewage overflowing into the river at times of heavy rainfall.