The Bohai Oilfield, located near the largest port city of Tianjin in north China, is expected to gain an annual drilling capacity of five million tons of crude oil by the end of this year, Local Officials said.

Local officials said that the second-phase project to expand the production capacity of the Suizhong 36-1 Oilfield in the Bohai Bay will be completed by the year's end, and will increase its annual production capacity from the current 1.5 million tons to 3.5 million tons.

The oilfield is the first in China with a verified natural reserve of 300 million tons.

When the entire project is completed, the total production capacity of the Suizhong Oilfield will reach five million tons, said Yu Yi, an official in charge of the expansion work.