As temperatures soared past 25C shark sirens rang out over the golden sands, urging ocean-goers to leave the water.
The warning broadcast said 10-15 hammerheads were spotted around 200 metres from the flag area of the beach, which is located on the northern beaches.
Lifeguards took to the water on jetskis to patrol the ocean.
Palm Beach is a popular spot made famous by soap opera Home and Away, as it’s the outdoor location used for the fictional town of Summer Bay.
Three species of hammerheads are found in Australian waters.
It’s unclear what species of hammerhead were sighted at Palm Beach.
Only the great hammerhead is considered dangerous, although attacks by the animals are relatively rare.
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