TOKYO (AFP) — When Takanori Kuzuoka began climbing the criminal career ladder, he didn’t fancy joining Japan’s old-school yakuza, with their tattoos, rigid hierarchy and codes of honor.

Instead he was drawn to the newer, tech-savvy “tokuryu” underworld, where shadowy criminal kingpins use social media and encrypted messages to recruit often naive foot soldiers to do their dirty work.

This new brand of Japanese organized crime has grown fast by creating its own criminal gig economy — with bosses insulated from arrest by disposable minions.

Kuzuoka gave Agence France-Presse (AFP) an extraordinary insight into the tokuryu mindset in a five-month exchange of handwritten letters from his prison cell.

While the yakuza used to pride themselves on not preying on the poor and weak, the tokuryu have no such scruples. They make much of their millions from conning Japan’s ageing population, while the yakuza — whose multi-billion-dollar empire is shrinking after years of strict anti-mafia laws — have traditionally scorned such fraud as dishonorable.

Despite their disdain for the new kids on the block, a high-ranking gangster allied to a major yakuza clan privately admitted to AFP that they were “losing their allure for young people.”

“Fewer recruits are signing up,” with millennials and Generation Zers not prepared to start at the bottom and work their way up, he said, in an interview that took months to set up.

They “don’t like being shackled” by its rules and rituals so “they’re increasingly choosing tokuryu instead,” he added.