Police on Saturday questioned the former manager of a corporate group that a third-party probe found had inappropriate transactions with a major fast-food gyoza chain over the arrest of a yakuza gang member concerning the fatal shooting of its president, investigative sources said.

The questioning was conducted on a voluntary basis after a third-party committee set by Ohsho Food Service Corp. looked into links between the operator of the restaurant chain "Gyoza no Ohsho" and antisocial organizations in March 2016.

A vehicle carrying Yukio Tanaka enters a police station in Kyoto on Oct. 29, 2022. (Kyodo)

The investigation found the restaurant chain made inappropriate deals with the head of a corporate group before the president took the helm in 2000.

The development comes after the Friday arrest of mobster Yukio Tanaka, 56, on suspicion of the 2013 murder of Takayuki Ohigashi, then-head of Ohsho Food Service.

Following his arrest, Tanaka was driven some 500 kilometers Friday from a Fukuoka Prefecture prison to a Kyoto police station for questioning, with the police apparently avoiding public transport to protect him from being attacked by other yakuza.

A police convoy took around 11 hours to transport Tanaka to Kyoto from the prison where he was serving time for a 2008 assault.

The vehicle carrying Tanaka, a senior member of a gangster group linked with the Kudo-kai crime syndicate, arrived shortly after 4 a.m. Saturday at the police station in Kyoto.

Tanaka is suspected of murdering Ohigashi with a firearm at a parking lot outside Ohsho Food Service's head office in Kyoto on Dec. 19, 2013.

There were concerns among police officials that Kudo-kai members could stage an attack to try to "eliminate" Tanaka before he could talk with officers about the Kudo-kai, an investigative source said.

"They (Kudo-kai) don't care at all about harming bystanders" to achieve their objectives, the source said.

The arrest came after the Kyoto police obtained expert testimony showing that traces of DNA from a cigarette butt found near the crime scene matched that of the suspect. The cigarette was the same brand as those Tanaka usually smoked at the time, investigative sources have said.

The police suspect that Tanaka was hired to kill Ohigashi, but have so far found no other connection between them, according to the sources.

In November 2020, a 10-year prison sentence was finalized for Tanaka for shooting at a company car that belonged to major general contractor Obayashi Corp. in Fukuoka in 2008.

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