Was Itcho Ito's killing a mob hit?

As mourners carry his coffin to its final place of rest, the Japanese press struggles to come up with convincing reasons for Tetsuya Shiroo's crime. Justin Norrie in Japan for The Sydney Morning Herald, reports:

Although yakuza groups have long-standing links to far-right nationalist groups, there is nothing to suggest the attack was politically motivated.

And:

There also were media reports that Shiroo had recently sent a letter to the broadcaster TV Asahi expressing outrage over money scandals linked to Mr Ito that involved hidden accounts and public works contracts.

Meanwhile, The Japan Times reports:

Former police officers in Osaka and Kobe, home to Yamaguchi-gumi, and reporters who cover the yakuza said they doubted Ito's murder had been sanctioned by the mob's top bosses.

Authorizing a hit on such a high-profile figure would invite a yakuza crackdown and would cause a groundswell of public support for tougher antigang laws, said one former Osaka police officer who asked not to be identified.