For nearly 60 years, Sydney did not record a single fatal shark attack.

Now the city has witnessed three deadly encounters in as many years, as well as two life-threatening ones in the last two days.

On Sunday, a 13-year-old boy was pulled out of Sydney Harbour by mates after he was attacked by what police believe is a bull shark.

READ MORE: Man charged with murder over a year after 60-year-old found dead on NSW South Coast

Another suspected bull shark bit an 11-year-old boy's surfboard on Sydney's Northern Beaches yesterday morning, and a man in his 20s was bitten on the leg at Manly the same day.

A fourth attack, this time on the NSW Mid North Coast, put a surfer in hospital with minor injuries this morning.

Encounters like these seem to be on the rise in NSW and across state borders, leaving some Australians afraid to even set foot in the ocean.

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