Chinese shares tumbled heavily on Wednesday with the benchmark Shanghai Composite Index nose-diving more than 3 percent immediately after midday break.
Earlier, the smaller Shenzhen index opened 0.44 percent higher at 9,525.61 points, Xinhua news agency reported.
The ChiNext Index, tracking China's NASDAQ-style board of growth enterprises, gained 0.16 percent to open at 1,997.32 points.
