SEOUL (AFP) - A coast guard helicopter transporting an emergency patient crashed off South Korea's south-west coast on Friday, local media reported.
The helicopter was carrying four people when it crashed into the sea off Gageodo Island as it attempted to land in thick fog, Yonhap news agency reported, quoting firefighter officials.
The helicopter was transporting a patient from the island to a hospital on the mainland when the accident occurred, officials said, according to Yonhap.
Search and rescue efforts have begun, but the fate of the four people on board, including the helicopter's two pilots, is still not known.
Officials fear heavy sea fog reported in the area may have caused the accident, the agency said.
A helicopter crashed into a residential district of Gwangju city last July as it returned from searching for victims of the Sewol ferry disaster. All five crew members were killed.