A search involving police, assisted by the Marine Area Command, LifeSaver21 helicopter, Surf Life Saving, and Marine Rescue NSW, began but was unsuccessful.
The search resumed at about 8am today, and at about 12.20pm, the body of a man was found.
While a formal process is yet to confirm the identity of the body, it is believed to be that of the missing swimmer.
The 30-year-old was swimming with friends at the southern end of Maroubra Beach on Sunday at about 4pm, but he failed to return to shore.
A report will be prepared for the coroner.
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