OREANDA-NEWS. February 02, 2015. China stocks resumed their decline, with investment sentiment dampened by fresh investigations into stock margin trading while Hong Kong shares were subdued.

The Chinese stock regulator is probing the margin trading business of 46 companies, the official Xinhua news agency said on Thursday, in latest efforts to rein in speculation.

The CSI300 index fell 0.8 percent, to 3,454.90 points at the end of the morning session, while the Shanghai Composite Index lost 1.0 percent, to 3,230.66 points, set for a fourth consecutive day of declines.

The CSI300 index is down 2.2 percent for January so far, its worst month since January last year.

"Sectors like finance, banking and insurance which benefited from an increase in margin trading have been particularly affected by the recent inspection," said Wang Xiaojun, an analyst at Xinda Securities.

China's banks are increasingly exposed to systemic risk as they seek to profit from the country's stock market frenzy by buying into the recent surge in margin finance.

But analysts don't believe this recent round of inspections marks the end of China's bull market.

"This inspection hasn't changed the direction of the market, just its current rhythm," said Wang.

The energy sub-index fell 0.9 percent and financials dropped 0.6 percent.

China CSI300 stock index futures for February fell 1.1 percent, to 3,454, -0.90 points below the current value of the underlying index.

The Hang Seng index dropped 0.1 percent, to 24,570.01 points.

The Hong Kong China Enterprises Index gained 0.1 percent, to 11,753.04.

The index measuring price differences between dual-listed companies in Shanghai and Hong Kong stood at 126.00.

A value above 100 indicates Shanghai shares are pricing at a premium to shares in the same company trading in Hong Kong, and vice versa.

Total volume of A shares traded in Shanghai was 15.38 billion shares, while Shenzhen volume was 9.24 billion shares.

Total trading volume of companies included in the HSI index was 0.6 billion shares.