Photo taken on Jan. 10, 2011 shows the Huizhou 21-1 oil field near south China's Guangdong Province. The China National Offshore Oil Corporation said late Dec. 19, 2011 a gas leak was found in a sub-sea gas pipeline of its Zhuhai Hengqin gas processing terminal. The oil giant said it has shut down relevant platforms in the Panyu 30-1 gas field and the Huizhou 21-1 oil field. (Xinhua/Liu Dawei)

ZHUHAI, Dec. 20 (Xinhua) -- CNOOC, China's largest offshore energy explorer, said Tuesday that gas is leaking out from one of its sub-sea pipelines in the South China Sea.

The leak was detected Monday by fishermen about 12 kilometers from its natural gas terminal in the city of Zhuhai, Guangdong province, said Gao Guangsheng, vice president of CNOOC's Shenzhen branch, which manages the terminal.

Fishermen detected the leak Monday morning after they saw water shooting out from the sea due to the pressure caused by the gas leak.

The leak might be caused by external factors, Gao said.

Gao said the situation is under control. No one was hurt, and there was no environmental damage.

The gas fields were shut down Monday after the company was notified of the leak.

The company is rushing to release the pressure in the leaking pipeline, which it expects to be done by Wednesday, and then it will start the repair work.

It will repair the pipeline to resume the operations at the terminal as soon as possible, as the outage could lead to gas shortages in Guangdong,said Lin Zhongming, director of the Shenzhen branch's Party committee office.

The Beijing-based CNOOC - China National Offshore Oil Corporation - will lose the equivalent of around 26,700 barrels of oil daily, Lin said.

The Zhuhai Maritime Safety Administration has issued notices to evacuate nearby boats and to inform local residents about the leak.