A search operation is currently underway to locate a swimmer who vanished at Maroubra Beach in Sydney.

Teams from Marine Rescue Botany Port Hacking and Marine Rescue Middle Harbour are working alongside water police in the effort to find the missing individual.

The swimmer, believed by authorities to be in his 30s, disappeared after entering the water shortly before 4 p.m. today.

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“Offshore conditions are challenging this afternoon, with choppy seas and intermittent rain showers,” stated Marine Rescue NSW Inspector Andrew Harding.

"Volunteer crews on board Middle Harbour 30 and Botany Hacking 32 will continue searching this evening until instructed otherwise by NSW Police Marine Area Command."

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