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."


Lancaster wills company donates thousands to help local community groups making a difference
Morecambe Bay Curriculum wins top award
Lancaster film director's latest action movie now showing in UK cinemas
Appeal after Jack Russell dog found collapsed in Lancaster
Lancaster food companies announced as finalists in new Taste Lancashire Producer Awards
New student apartments block opens in Lancaster
Former BBC reporter and ex-Heysham shipping chief launch popular maritime podcast
Lancaster children get life-saving advice at 'Crucial Crew' water safety event
Crews tackle house fire in Heysham
Police appeal after 20 motorbike thefts in 30 days in Lancaster and Morecambe area
Truck driver jailed for causing death of six-year-old Lancaster girl
Former Morecambe Football Club co-chairmen break silence after shock resignation from board
Royal Lancaster Infirmary ward closed to visitors due to norovirus outbreak
Morecambe Football Club stalwarts resign from board
Heysham coffee shop couple take over Morecambe craft ale bar
Morecambe seafront cafe reopens
Eighty new houses in Halton recommended for green light
More than 600 knives recovered in area including Lancaster district as part of police national crackdown
Extra urgent NHS dental appointments now available in Lancaster district
New wellness cafe opens in Lancaster city centre

