A tourist has spotted a "huge" shark swimming around a harbour during high tide this week.

Olga Bates, 46, was visiting St Ives in with family when they saw the large sea beast near boats.

The group spotted the shark at 6.26am on Wednesday (March 23) during high tide.

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

Olga from Knighton, Wales, said minutes before they saw a group of seals ''hiding'' from the shark.

The 'huge' shark was in the harbour at St Ives (Image: Olga Bates / SWNS)

She said: "We had been very lucky.

"We woke up so early to watch the sunrise and spotted seals hiding under the bridge and then we saw what they were hiding from - the shark.

"It was amazing to see and it was so close to the beach. I was an amazing surprise for us, we have never seen one that close before.

"We were enjoying the views and the sunshine, we were overwhelmed."

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Olga added: "It circled around the harbour a couple of times, we estimate it was around 10ft, it was longer than some of the boats.

"We were down there for around an hour and a half until the water started to do down.

"As soon as the water started to go down we knew it would be gone already.

''It was amazing to see it so close, I was so lucky and my grandson was very excited."