China has sentenced to death two leaders of a gang which stole crude oil by drilling into pipelines, causing 400 million yuan ($53 million) in damage, the Xinhua News Agency said on Saturday.

A court in Dongying city, in the eastern province of Shandong, gave a suspended death sentence to another gang member on Friday and sentenced seven others to prison terms ranging from three years to life.

In 2005 the gang slipped into a seabed oil extraction centre at China's Shengli oilfield and drilled into a pipeline, but fled when they found it contained natural gas instead of oil. A month later, they stole 10 tons of crude oil from a nearby pipeline, Xinhua said.

The holes in the pipes were not discovered until months later, by which time the leaks had disrupted local fisheries.