Allegations that the national women's judo coach used a bamboo sword to beat his athletes, including some Olympians, are the "gravest crisis" to hit Japanese sport, the education minister said Tuesday.
Former world champion Ryuji Sonoda resigned in humiliation last week after admitting that claims he had physically and emotionally abused 15 of the country's top sportswomen were "more or less true".
The explosive claims have rocked a nation accustomed to greatness in judo, and come as Tokyo seeks to persuade Olympic bosses it should be allowed to host the 2020 Games.
"The incident is the gravest crisis in Japan's sporting history." Education Minister Hakubun Shimomura told reporters.
"We should not shy away from the facts and should review not only judo but all sorts of sports to see whether they have overlooked violence in the name of achieving sporting excellence.
"This is the time that Japan can show both to those inside and outside the country that it has abandoned all violence in sports," Shimomura said.
He said Japan's many sporting associations each needed to set up a hotline for athletes who had concerns and should review the ways coaches are educated.
The scandal claimed another scalp Tuesday when Kazuo Yoshimura, the head of training at the All Japan Judo Federation, announced he was stepping down.
"I would like to make a heartfelt apology for my poor supervision," he told a press conference
Acting women's national head coach Masaru Tanabe on Tuesday vowed he would go all out to provide an opportunity for athletes "to be able to give their best performances", as the team flew to Europe for an international competition.
In a sports policy conference held by the ruling Liberal Democratic Party on Tuesday, some participants expressed concerns about the scandal's negative impact on Tokyo's bid for the Olympics, public broadcaster NHK reported.
In an interview with AFP Friday, Japanese Olympic Committee president Tsunekazu Takeda, who is also the Tokyo bid chief, rejected speculation the scandal could give a bad impression of sport in Japan.
He insisted the necessary changes were being made.
"In response to the problem, the head coach is being changed and I believe the judo federation will quickly move forward with its internal reform," he said.
The 100-plus members of the International Olympic Committee will gather in Buenos Aires on September 7 to vote on which city -- Madrid, Istanbul or Tokyo -- should host the 2020 Games.
The bullying scandal added fuel to a debate over corporal punishment in Japan following the suicide of a schoolboy who had been repeatedly hit by his basketball coach.