Japanese Cybercrime Expert Killed by Man He Argued with Online

Japanese cybercrime expert and blogger Kenichiro Okamoto was reportedly stabbed and killed after giving a seminar on “how to resolve Internet disputes,” by a man he had argued with online.

“The suspect, Hidemitsu Matsumoto, allegedly followed Okamoto into the toilets after he had ended his talk at a venue in the south-western city of Fukuoka. Okamoto was stabbed several times before staggering out of the toilets after his assailant, who fled on a bicycle,” reported the Guardian. “Okamoto, who sustained stab wounds to the chest and neck, was taken to hospital where he was confirmed dead. His attacker reportedly handed himself in almost three hours after the attack.”

“Moments before the fatal stabbing, the 41-year-old had shared advice at a public event on how to deal with online disputes,” the Guardian continued, adding that Matsumoto confessed to hating and holding a “grudge” against Okamoto.

On the event’s official page, Okamoto advertised the seminar at, “People who like fire and net trouble,” and, “Those who like internet more than three times of rice.”

“When I have been working as a net watcher for many years, I encountered various cases such as flames on the Internet and trouble,” Okamoto declared. “Sometimes I participated and I got various knowledge.”