China's Shanghai Stock Exchange said Friday it is probing into the slow confirmation of stock transactions found after the opening of Friday's morning session.

The exchange will continue to keep investors informed, and investors may contact their designated securities firms for assistance if they encounter any problems or have any questions, it said in a statement.

China's major stock indices surged in the morning session Friday. The benchmark Shanghai Composite Index rose 2.14 percent to 3,065.29 points at midday, and the Shenzhen Component Index soared 6.37 percent to 9,484.81.

The country's stock market has been on a rising streak over the past few days with heavier trading. The turnover of stocks covered by the two major indices surpassed 1 trillion yuan (about 143 billion U.S. dollars) for the second consecutive day.