A 20-tonne sperm whale carcass has been towed along the NSW South Coast, sparking an urgent shark warning for local swimmers and surfers.

Because there is no vehicle access to the remote beach, authorities were forced to wait for ideal conditions to remove the mammal by sea.

Watch the video above.

Dozens of onlookers gathered as the towing operation unfolded. (Illawarra and surrounds marine life sightings)

A removal operation finally began at dawn, with tugboats hauling the whale more than 20 kilometres south before it was hoisted from the water at Bellambi Beach this afternoon.

It was then taken to the Whytes Gully waste facility in Wollongong.

Sperm whales are the largest toothed predators in the world. (Illawarra and surrounds marine life sightings)

Dozens of onlookers gathered as the towing operation unfolded, with many unable to stay long due to the overpowering smell.

Albion Park man Darren Malone, 47, estimated that at least 60 people had turned out, but he was left “gagging” as the stench from the decomposing carcass intensified.

Beachgoers have already been forced to evacuate the water following this morning’s removal. (Illawarra and surrounds marine life sightings)

NSW National Parks and Wildlife Service (NPWS) Area Manager Brendon Neilly said the lack of access and the scale of the task made it an enormous undertaking.

“The location, size and distances made it one of the most challenging operations of its kind,” he said.

Attention has now turned to the coastline between Stanwell Park and Bellambi Point, where Surf Life Saving Illawarra says the carcass has already attracted several sharks.

Seven sharks were spotted between Woonona and East Corrimal, prompting the duty officer to evacuate people from the water.

A Surf Life Saving Illawarra spokesperson said a UAV drone has been deployed for surveillance, and beach signage has been erected advising the public to remain out of the water until at least Monday.

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