A dead sperm whale has been found on a sandbar in the North Sea, but experts said it was unclear if it died as a result of stranding.
It was spotted about one mile (1.6km) off the Norfolk coast in The Wash.
The monitoring group Norfolk Cetaceans said it was probably a young male, but the cause of death was unknown.
Staff at the RSPB Snettisham reserve said they reported the sighting to the coastguard and the UK Cetacean Strandings Investigation Programme.
HM Coastguard at Hunstanton said on social media that a boat was sent to look for the whale on Monday evening, but they could not find it due to "its possible location, state of the tide and it being night-time".
Photographs were taken of the animal the following morning.
Carl Chapman of Norfolk Cetaceans said it was rare for sperm whales to enter the shallow waters of the North Sea.
He said there had been a proliferation of squid this year and thought the whale may have been tempted into chasing them into the southern North Sea.
He added that it seemed the dead sperm whale was the only example that had gone astray, as there had been no reports of others being stranded off the UK or other countries on the southern North Sea.
In 2016, 26 sperm whales were found stranded along UK and European coastlines in the North Sea.
Scientists thought those whales could have taken "a wrong turn" to find food.
The UK Cetacean Strandings Investigation Programme (CSIP), which recovers and investigates corpses, has been contacted for comment.
According to CSIP, approximately 500 cetacean strandings are reported around the UK each year.
The majority of these are dead, with a small proportion found alive.
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