BEIJING, CHINA - THE Chinese government's investment arm began buying shares in three of the nation's top banks on Thursday in a bid to boost their market prices amid a plunging stock market, state media said.

Central Huijin Investment Co. Ltd. said it would buy shares of Industrial and Commercial Bank of China, Bank of China and China Construction Bank, Xinhua news agency reported, adding that 'operations had started on Thursday'.

The move was to 'shore up their share prices amid stock market slumps", Xinhua said.

Cash-rich Central Huijin was set up earlier this decade charged with reforming state-owned banks burdened with a high ratio of non-performing loans.