The bodies of a 35-year-old man and his five-year-old daughter have been found in waters off the coast of South Australia's Eyre Peninsula.

Key points: A search operation is underway to retrieve the bodies from the water

A search operation is underway to retrieve the bodies from the water The incident occurred at Cape Carnot in South Australia

The incident occurred at Cape Carnot in South Australia The ABC understands there have been six drownings in the area

Police say the pair, who were from Adelaide, were swept from the rocks at Cape Carnot — about 40 kilometres south of Port Lincoln — this afternoon.

The bodies have been sighted from the air, with a major operation underway to retrieve them.

An alarm was raised at about 1:30pm on Sunday after the pair was swept away near Whaler's Way Sanctuary.

Emergency services rushed to the area and commenced searching by land, air and sea, but rough conditions and communication issues reportedly hampered efforts to retrieve them.

The Police Helicopter Sea Rescue Squadron was also reported to be assisting with the search.

Port Lincoln police said it was preparing a report for the coroner in a statement.

Glenn Theakstone, co-owner of Whaler's Way Sanctuary, claimed the victims had been trying to get a photo of themselves with large waves breaking behind them when they were swept off the rocks.

He said: "Luckily there was actually another local person there, or family, with friends from Port Augusta … and the young fellow managed to stop a third bloke trying to jump in to save them otherwise there would have been three on the day."

Describing the swell as "extremely dangerous", he added: "You had about a 4.5 metre swell coming on with a bit of a south-west breeze so the white wash was up.

"They were warned at the gate not to enter into the caves, or go looking for the caves due to the sea's state — they obviously didn't adhere to that warning.

"They had their backs turned to the sea while a third person was trying to take a photo of the waves smashing up behind them and of course anyone who knows anything about the ocean knows that the Great Australian Bight's well known for that one rogue wave — every half a dozen sets or couple of sets and that one has come through and actually swept them off the rocks.

"The force of that wave — you'd have really no hope.

"Unfortunately if people would just stop, read the warning signs, read the permit they were issued, I'd say all of these deaths wouldn't have happened.

"They were physically warned by a gatekeeper on the day. There's warning signs all the way, there's warnings written into the permit you buy, there's also warnings at the location that they've walked past, they've also walked past the plaque commemorating the last death in that location," he said.

Cape Carnot is a notoriously dangerous spot, with warning signs on the headland and pamphlets highlighting the dangers given to visitors.

The ABC understands there have been six drownings in the same area.