Sports minister Yoshiaki Takaki on Tuesday asked all parties in the sumo match-fixing scandal to cooperate with investigators after learning that some people under suspicion may have broken or changed mobile phones with possibly incriminating text messages.
"We hope those involved will squarely answer questions, so we can have the earliest full-scale disclosure of the facts," Takaki said.
The biggest crisis to ever hit the sport has resulted in the cancellation of next month's tournament.
Of the 14 people being investigated so far, some appear to have been uncooperative, saying their phones were broken or they had bought new ones.
"Everyone in sumo circles aspires for the best and has worked hard to develop sumo. Sumo is in crisis. I hope that everyone can return to their roots and make a fresh start," he said.
Takaki, however, denied that the Ministry of Education, Culture, Sports, Science and Technology is considering recruiting a chairman from outside the sumo world, as some media reports have suggested.
"The sumo association is its own entity. Its independence and autonomy should be respected. This is not a discussion about telling the sumo world to do this or that from outside," he said.
Meanwhile, questioning of wrestlers in the top makuuchi and juryo divisions began Tuesday and should conclude before the week is out.
The probe was originally supposed to start Monday and run through Feb. 21, but extra staff has been added to the investigative panel.
The last tournament to be called off was in 1946, but that was so repairs could be made to the main sumo arena.