A slick has been discovered off the coast of Whitehaven.
Whitehaven Harbour Commissioners said its team and partners are currently investigating the situation.
The commissioners said it must be treated as a formal pollution event until it is identified.
It is not yet known if the slick is a natural phenomenon known as a red tide, also known as a harmful algal bloom.
A spokesman said: “We’re liaising with the relevant authorities and agencies, and updates will follow once we know more.”
