China's benchmark Shanghai stock index closed down 3.42 percent on Thursday, as worries persisted over the weak economy and currency, dealers said.

The Shanghai Composite Index slumped 129.82 points to 3,664.29 on turnover of 501.2 billion yuan ($78.4 billion).

The Shenzhen Composite Index, which tracks stocks on China’s second exchange, dropped 3.00 percent, or 66.56 points, to 2,155.49 on turnover of 480.9 billion yuan.