Mainland stocks fell on Wednesday on concerns about tighter liquidity, a fresh slide in oil prices and worries that Chinese regulators were intensifying scrutiny of insider trading.

The benchmark Shanghai Composite Index declined by 1.41 percent or 47.22 points to 3,305.74 points on Wednesday. The Shenzhen Component Index fell by 1.71 percent or 197.67 points to 11,354.20 points.

The CSI 300 Index of the biggest companies traded on the bourses in Shanghai and Shenzhen dropped by 1.39 percent to 3,525.32 points.

Total turnover on the two bourses on Wednesday was 606.47 billion yuan ($97.08 billion), down from Tuesday's 729.06 billion yuan.

Securities regulators have commenced reviewing every instance of a share sale in which a designated company insider managed to sell at the top of a price spike, the official China Securities Journal reported on Wednesday.

Oil and nonferrous companies were down 2.51 percent and 1.8 percent on average, respectively. PetroChina Co fell by 2.85 percent to 12.25 yuan and Sinopec dipped 2.16 percent to 6.34 yuan. 

Banks and insurers also fell on Wednesday. China Pacific Insurance (Group) Co closed down 4.35 percent at 34.75 yuan, leading the sector's 3.70 percent fall. China Minsheng Banking Corp fell by 2.45 percent to 9.94 yuan, while the overall banking sector declined by 1.42 percent.

ChiNext, China's NASDAQ-style board for high-tech and fast-growing start-ups, fell by 0.70 percent or 12.26 points to 1,731.41 points.

In Hong Kong, the Hang Seng Index edged up by 0.22 percent to 24,861.81 points, with total turnover of HK$80.37 billion ($10.37 billion).

Reuters - Global Times