Japanese police for the first time ever sought criminal prosecutions of nine sumo wrestlers and sports figures in a damaging scandal over illegal gambling and yakuza mob ties.
The ancient and highly ritualistic national sport is already under the spotlight after news of illegal drug use, brutal training methods and in recent weeks claims of bout-rigging.
Police handed files to prosecutors outlining claims that five active wrestlers, three patrons or financial supporters, and one member of a crime syndicate were involved in gambling on baseball games, the Sankei daily said.
Betting in Japan is allowed only on horse racing and some motor sports.
Prosecutors must now decide whether to indict and try the nine, who were not named by police or in Japanese media reports.
It is the first time in the history of sumo -- a sport which dates back some 1,500 years -- that Japanese police handed over a case to prosecutors against serving sumo wrestlers, local media said.
Last year, scores of sumo grapplers, who are expected to act as role models in Japan, admitted to betting illegally on baseball in gambling rings that were allegedly organised by bookmakers linked to organised crime.
Reportedly about 30 more sumo figures, including the now expelled but formerly high-ranked "ozeki" wrestler Kotomitsuki, have admitted to involvement in gambling, and local media have speculated that more will face prosecutors.
This month sumo authorities had to call off the spring tournament over the match-fixing scandal, the first such cancellation in over half a century.
At least 14 mid-ranked wrestlers stand accused of bout-rigging and three have admitted to fixing fights and trading wins after incriminating cellphone text messages obtained by police were leaked to the press.
Police found the evidence indicating bout-rigging during the investigation into illegal baseball gambling, but they are not investigating these claims because fixing sumo bouts is not a crime.