A tourist has captured exciting footage of a basking shark swimming around a harbour in Cornwall.

Olga Bates, 46, was visiting St Ives with family when she saw the large creature during high tide on the morning of Wednesday 23 March.

Experts say it was a basking shark - the second largest type behind the whale shark - that can grow up to 45ft.

They are relatively harmless to humans, with many in UK waters feeding on plankton and small crustaceans.