[Updated 9:15 p.m.] Read the full CNN.com story

Some 123 people were trapped in a Chinese coal mine after it was flooded Sunday, state-run media reported.

Mine workers became trapped in the Wangjialing coal mine in China's Shanxi Province when underground water gushed into the mine, the official Xinhua news agency reported, citing the provincial work safety supervision administration.

Officials said more than 100 workers were rescued from the mine, but another 123 remained trapped inside. Officials originally estimated that 152 people were trapped inside.

The cause of the flooding was not immediately known.

The mine is a key project approved by the provincial government in a coal-rich area, Xinhua reported.