A shark measuring around 120cm/4' in length was filmed swimming at low tide at Cattawade Sluice, near Brantham, Essex - ten miles inland.
The shark, believed to be a Starry smooth-hound or hound shark, was spotted by Jody Gibbons while out walking at the weekend. He said it appeared to be looking for an exit back into the River Stour.
Mr Gibbons says he took the footage of the shark to prove to friends he'd seen it, thinking they wouldn't believe him otherwise!
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