Oil has spilled into a river in East Sussex, creating a slick that spans around six miles, it has been reported.
Officers from the UK's Environmental Protection Agency (EPA) are currently working to clear the oil, to which it was alerted by members of the public and local residents.
A spokesman for the EPA stated: "Due to our prompt efforts, the impact of the pollution on the environmentally sensitive River Ouse has been greatly reduced."
He thanked the public for the calls and said their raising the issue quickly allowed the agency to "respond quickly" and install oil booms to reduce possible damage.
An investigation into to the source of the oil is currently underway, although it is believed to be the kind used in central heating systems.
This is not the first oil spill to occur in Europe of late - on a larger scale, around 300 tonnes of oil was leaked into the Irish Sea earlier this week and its movement is currently being monitored by the Irish Coast Guard.