A dog walker has expressed concern after returning from the beach to find her pet was covered in oil.

Katie Johnson, 26, who lives in Horsley Drive, Gorleston, was walking her golden retriever, Ralph, along the shore on Monday evening.

When she got home she thought his coat was covered in mud so she washed him in the bath but the substance was sticking to his fur.

After smelling it she noticed an oil smell and looked backed at photos (pictured above) she took of Ralph that evening on the beach and noticed a dark black splodge on the sand.

Miss Johnson said: 'I did not see at the time but there was quite a lot of oil on him. I had to bathe him quite a lot to get it out. Don't take your dogs down to the beach until this has been checked.'

She contacted the Environment Agency to let them know what she has seen.

David Wiles, a spokesman for Great Yarmouth Borough Council, said: 'Officers visited the beach at the weekend, and yesterday afternoon (February 10). Despite the high winds, none of the trenches have been exposed over the last three days.

'The incident posted on Facebook seems to be isolated as no other reports have been received. It is not clear where the reported oil has come from, although it could be the remnants of last month's exposure.

'Environmental Services has discussed this report with the Environment Agency and will continue monitoring the beach. Environmental Services will also seek to speak with the dog walker to discuss the situation.'

The oil could be that from the Eleni V oil tanker disaster, in 1978, which was buried in trenches that had been dug at the back of beaches, which was a Government-approved method of disposal at that time.

In January 2013, storms temporarily exposed four trenches on a relatively isolated area of beach between Gorleston and Hopton, which is the first exposure of the trenches recorded by the borough council.

Trenches are temporarily exposed when certain weather conditions result in a drop in beach level. However the trenches are normally covered again by sand within a few days as beach levels recover.

Mr Wiles added: 'The borough council's policy is to monitor the trenches and the weather conditions – and deal quickly with any exposures. This approach worked well last month, which saw warning signs erected swiftly and the beach mechanically cleaned following the first major exposure in three years.'