Johannesburg - A man has gone missing at sea in Merebank, Durban on Thursday, LifeSaving SA said."The 25-year-old man from Johannesburg was at the non-swimming beach with friends when he was caught in a rip current," the organisation said in a statement."The man struggled against the current, then tragically lost his bodyboard. His body disappeared below the surface before the rescue services arrived on the scene."A search by lifeguards was unsuccessful in locating the man. The search would continue on Friday, LifeSaving SA said.The Cutting beach, where the incident happened, has a clear signpost that showed the beach is not protected by Lifeguards, it said.The organisation urged holidaymakers not to swim in an area not protected by lifeguards.