A visitor from South Carolina was seriously injured while in waters off East Oahu on Thursday, the Honolulu Emergency Services Department said.
Rescuers responded around 12:40 p.m. to reports of two swimmers in distress who had jumped into the water at China Walls.
Officials said a lifeguard swam roughly 200 yards to rescue both people, who were treading water.
Paramedics treated the 29-year-old man who had swallowed water and was extremely exhausted. He was transported to the hospital in serious condition.
The other patient was uninjured.
Surf on Thursday was 4- to 6-foot faces.
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