BEIJING - China Securities Regulatory Commission (CSRC) will increase checks on program trading blamed for some of the recent stock market volatility.

CSRC spokesperson Zhang Xiaojun said Friday the agency is examining some cases, and both Shanghai and Shenzhen exchanges have restricted 24 accounts suspected of disturbing share prices or misleading other investors by frequent orders and cancellations.

Program trading usually focuses on a basket of stocks with buy and sell orders executed by a computer program based on predetermined conditions. Program trading amplifies gains and losses and increases market fluctuations.

The CSRC and bourses are verifying the real name of the accounts and analyzing their capital sources and trading strategies to assess the effect on volatility, with targeted measures planned, based on the results.

China's stock market went through a roller-coaster ride this week, with a record plunge on Monday in the past eight years and a rally on Wednesday.

The benchmark Shanghai Composite Index opened 1.35 percent lower at 3,655.67 on Friday.