China Coast Guard vessels rescued two Vietnamese sailors late Sunday in the South China Sea, bringing the number of Vietnamese nationals saved by Chinese rescuers in recent days to 47, Chinese maritime authorities said Monday.

The rescue operation came after the Vietnamese-flagged vessel Khoi Nguyen18 sank late Thursday near Yongshu Reef. On Saturday, the rescue ship Nanhai Jiu115, operated by the Ministry of Transport's South China Sea Rescue Bureau, had already recovered multiple survivors in the area.

The two crew members spotted on Sunday were pulled from the water by the Chinese coast guard vessels Xuande and Nansha near the Nansha Islands, according to Sansha's maritime safety administration. Both were in stable condition, officials said.

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China Coast Guard said it dispatched two vessels to the search zone after receiving a notification from the Hainan provincial maritime search and rescue center. The two latest survivors were transferred to the command vessel Nanhai Jiu115 on Monday for further care. Previously rescued crew members will gradually be handed over to Vietnamese authorities at sea. Search efforts remain ongoing.