SoftBank Group Corp. said Wednesday it will acquire US investment firm Fortress Investment Group LLC for around $3.3 billion as it prepares to launch an international investment fund, according to Japan's News Agency (Kyodo).     SoftBank is aiming to tap into the investment know-how of Fortress.

     The Japanese telecommunications giant said last October it will launch the $100 billion investment fund with Saudi Arabia's sovereign wealth fund and other potential partners. Other investors are planning to join the acquisition as well.

    The percentage of investment by SoftBank will be decided later. The transaction is expected to be completed by December