Dog walkers have been told to keep dogs on lead after lumps of solid palm oil began washing up on beaches.
A social media post from Selsey Coastguard Rescue Team reads: "DOG WALKERS BEWARE! Waxy substance found on nearby beach.
"We can confirm that we have received reports of an unconfirmed waxy substance washing up on Bognor beach. Littlehampton Coastguard Rescue Team have shared this information and The Local Authority have been informed so they can arrange for its removal.
"As a precautionary measure we are advising that people visiting the beaches in our area please keep their dogs within sight, preferably on leads, until we have further information about what the substance is.
"Remember that if you see anything out of the ordinary washed ashore to please call 999 and ask for the Coastguard so that we can investigate it."
Arun District Council confirmed that the substance being washed up on the beaches was solidified palm oil but said it was not toxic to humans.
A spokesman for Arun District Council said: "This happens from time to time, particularly after stormy weather. Palm oil is not toxic to humans and can be disposed of with normal waste. However it is important to note that this substance may be hazardous to dogs so we urge owners to be careful if walking their pets on the beach at this time."