NANNING - Three fishermen were rescued and three remain missing after a boat sank off the coast of South China's Guangxi Zhuang autonomous region early Saturday morning, according to local maritime authorities.

The three crew members saved by nearby fishing boats were under treatment at a local hospital, but their lives were in no danger, the Beihai maritime search and rescue center said in a statement.

The fishing boat sank around 5 am after being hit by sudden strong gales, with the crew being left with no time to wear life jackets.

The rescue operation involving the center's rescue vessels and helicopter as well as fishing boats in nearby waters is still under way.