Prosecutors questioned executives from Shimizu Corp. and Taisei Corp. on a voluntary basis following alleged bidding obstruction by Obayashi Corp. in connection with the maglev train project, sources said Wednesday.
The three major construction firms and Kajima Corp. won contracts for 15 out of 22 projects related to the advanced high-speed train system that is expected to enable travel between Osaka and Tokyo in about an hour.
A special investigation squad from the Tokyo District Public Prosecutors Office has already quizzed executives at Obayashi and Kajima over alleged fraud in the bidding process where an Obayashi-led consortium won a ¥9 billion ($79 million) contract in April 2016 to build an emergency exit.