People have been advised to avoid the beach at Half Moon Bay at Heysham after an apparent oil spill.
Lancaster City Council said there has been "a pollution incident" affecting beaches and water in the area.
They have asked people to stay away from the area until further notice while a clean up takes place.
The council said that responsible authorities were aware and are investigating.
"Our advice is to avoid the beach until further notice as residual contamination may still be present," said a Lancaster City Council public notice.
"Please avoid all contact with visible tar/oil on the beach and in the water.
"Please report any new contamination to Lancaster City Council on 01524 582000."
The photos below are from Half Moon Bay beach on Friday.


A Lancaster Police spokesperson said on Saturday: "Please be aware that Lancaster City Council along with other agencies are currently dealing with what looks like an oil spill on the beach at Half Moon Bay in Heysham.
"Please avoid the area where possible."


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