Police on Friday questioned sumo grand champion Harumafuji on a voluntary basis over an allegation he assaulted a lower-ranked wrestler during a drunken brawl.The government the same day expressed regret over the case engulfing the traditional Japanese sport, which was recently regaining its popularity after its reputation was tainted by scandals over match-fixing, violence and bullying.According to investigative sources, the 33-year-old yokozuna allegedly hit 27-year-old fellow Mongolian wrestler Takanoiwa in the head at a restaurant-bar around the night of Oct. 25 in the western Japan cit…READ FULL ARTICLE