South Korea's presidential Blue House starts to investigate the reason of networks paralysis immediately after the country's computer networks of the main broadcasters and banks were completely paralyzed Wednesday, the Yonhap News Agency reported.The Blue House said they are figuring out whether networks paralysis in broadcasters, bankers is relative with the Democratic People's Republic of Korea (DPRK).The computer networks of KBS, MBC and YTN, and those of two banks, Shinhan Bank and Nonghyup, were totally stopped at about 2 p.m. local time Wednesday, according to reports.The police has not found the exact reason of the paralysis but said earlier that it seemed like to be a cyber attack.