WORKERS at a warehouse were shocked when raw sewage flowed down the road.

The incident happened near Kenley Warehousing and Distribution at Darwen Mill on Hilton Street at dinner time yesterday.

Managing director of the company Chris Clay said that it was a "complete mess and an environmental disaster."

He said the problem had been going on for a few weeks and waste from a drain had spilled out with human waste being one of the items flowing down the street.

Blackburn with Darwen council's drainage department were called out to deal with the clean-up operation. A council spokesman said United Utilities was investigating the incident.

A spokesman from United Utilities said the council was called out as it manages drains on its behalf and United Utilities trade effluent controllers also dealt with the incident. The spokesman said there a partial blockage of the system at the junction of Tower Road and Hilton Road.

This had been caused by fat deposited in a sewer from an unknown source -- the large amount of fat had caused the sewer to overflow and made the road slippery.

The spokesman said the fat had been cleared away at noon yesterday.

The road had to be made safe as it was slippery and sand was laid down on the road.

The spokesman added that United Utilities were investigating the source of the fat and that it would be a mixture of household waste which would have overflowed.