Photo/Illutration Riot police stand guard outside the headquarters of a yakuza gang in Kasuga, Fukuoka Prefecture, during a search on Nov. 3. (Noriki Nishioka)

KASUGA, Fukuoka Prefecture—Police on Nov. 3 searched the headquarters of a yakuza gang whose member has been arrested over the 2013 killing of a company president known as the “Gyoza King.”

About 40 officers from the Fukuoka and Kyoto prefectural police departments entered the headquarters at 9 a.m. and spent about two hours searching the building.

They emerged with three plastic cases of items seized from the headquarters, which is also the home of the gang leader in a quiet residential area.

Yukio Tanaka, 56, a high-ranking member of the gang, an affiliate of the Kudo-kai syndicate, was arrested on Oct. 28 on suspicion of murdering Takayuki Ohigashi, president of national restaurant chain Ohsho Food Service Corp., in Kyoto.

Ohigashi was 72 years old when he was gunned down on the morning of Dec. 19, 2013.

Tanaka, who was serving time in Fukuoka for an earlier crime when he was arrested, was connected to Ohigashi’s death through a DNA test on a discarded cigarette butt found at the scene.

However, investigators still have not established a motive for the attack.

Officers have asked former executives of Ohsho Food Service, which specializes in serving gyoza dumplings, about any possible inappropriate business transactions when they were in charge of the company.

Although the company has denied any ties with organized crime, shady business transactions left the company with large losses that Ohigashi had to eventually clean up.