The second in command of Japan's biggest yakuza crime organisation was convicted of extortion yesterday.

Kiyoshi "Mekkachi" Takayama, 65, who reputedly lost the use of one eye in a swordfight early in his career, was jailed for six years.

His underworld nickname of "Mekkachi" means "one-eyed" in the dialect of western Japan.

Takayama is second in command of the Yamaguchi-gumi, a vast organised crime syndicate that had 27,700 members at the end of last year, according to the National Police Agency.

He had been on 1.5 billion yen (HK$122 million) bail for treatment of an illness since June last year. It was one of the highest bonds ever set by a Japanese court.

Throughout his trial in the western city of Kyoto, the mobster had denied extorting 40 million yen from a local construction company with the help of an affiliated gang boss, reports said.

Presiding judge Akihiro Ogura told the court: "The constructor's testimony that he had been the victim of extortion by the defendant is credible."