The skipper of an abalone fishing boat watched in horror as one of his divers was taken by two great white sharks off South Australia's Eyre Peninsula late yesterday.

The search is resuming for the body of the man, who was taken out to sea by the sharks after being attacked as he returned to the boat.

The attack happened near Coffin Bay at the foot of the Eyre Peninsula, south of Perforated Island.

Police say the boat's skipper is suffering from "significant shock" and had been unable to give many details about the attack.

This morning Inspector Brenton Saunders told ABC News Breakfast that the search for the man's body had to be curtailed in fading light last night but will resume this morning.

Police, SES and fisheries officials will be on the water to scour the site of the attack.

The abalone boat was removed from the beach last night and is being inspected by police.

Inspector Glen Sickerdick from South Australian Police Communications says detectives will be conducting an investigation into the incident.

"At this stage we haven't recovered the body. The body didn't return to the surface once it was taken by the sharks," he said.

The president of the Abalone Industry Association of South Australia, Jonas Woolford, says local abalone divers have been rocked by the event.

"They're all extremely upset about it, most of them were all out diving as well. It is devastating what's happened. Our own diver's been taken by a shark," he said.

The Point Avoid region is notoriously rough and known for sharks, and there has been a big increase in shark sightings in recent weeks on the Lower Eyre Peninsula.

Two weeks ago the ABC was told of one diver who ducked to avoid a five-metre white pointer.

He was brushed by the shark as it swam away.