China succeeded in its first 300-metre saturation diving on Sunday morning as three divers returned safe and sound from deep water to the living chamber on the ship.

The diving bell actually reached 313.5 meters deep under the South China Sea, according to Guo Jie, on-site chief director of the experiment.

The three divers, Hu Jian, Guan Meng and Dong Meng returned to the deck of the ship at 5:09 am Sunday.

The saturation diving technology enables human beings to withhold high deep water pressure by saturating the inert gas in human tissue fluid, according to Guo.

Three other Chinese divers planned to try again at 8 am Sunday and are expected to return to the living chamber at about 2 pm and stay there until January 24 to let the inert gas in their tissue fluid to return to normal pressure, said Shen Hao, director of Shanghai rescue and salvage center.

China is now working on the development of technology of saturation diving of 500 metres deep under sea, said Wang Zhenliang, director of the China Rescue and Salvage of the Ministry of Transport.