The National Sea Rescue Institute (NSRI) is searching for a fisherman who fell off an open fishing boat two nautical miles south of Arniston in the Southern Cape.
The incident happened on the seaward side of Saxon Reef on Friday morning.
"The sea rescue craft Spirit of Agulhas was launched and on arrival on the scene an extensive search operation commenced for a 41-year-old fisherman," the NSRI's Craig Lambinon said.
"Despite an extensive sea and shoreline search operation no sign of the missing fisherman has been found," he said.
A police dive unit was continuing with the search operations and an investigation has been opened.
On Monday NSRI officials were alerted to a body floating in the water offshore of Mossel Bay Point by the Transnet National Ports Authority following an eyewitness report.
The police were immediately notified and they retrieved the as yet unidentified body.
An inquest docket was opened.
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