HUMAN waste has been dumped in a stream in the Bradford district.
A lorry was spotted leaving the scene after contents of a septic tank were pumped into the beck, in Station Road, Oxenhope.
Yorkshire Water is investigating the incident, which happened at about 11am last Wednesday.
One villager, who didn't want to be named, said he'd seen the effluent being piped into the waterway.
"It was absolutely disgusting," he said.
"The stream is usually clear, but it was brown and littered with debris.
"I assume whoever was responsible was wanting to save on the cost of properly disposing of the waste."
Village parish councillor, Penny Cusdin, said: "This kind of thing could potentially pose a health risk. It is a concern."
Yorkshire Water has moved to reassure the public.
"Water samples taken from the beck have returned normal results and we are organising for a litter-pick to remove any remaining debris," said a spokesman.
"Unfortunately we cannot track the offending vehicle, but would encourage residents to remain vigilant and – if the vehicle returns – to contact us with the registration number."