Kenichiro Okamoto, better known by his blogger name Hagex, died on Sunday evening after reportedly being attacked by a man he had argued with online.

The suspect, Hidemitsu Matsumoto, allegedly followed Okamoto into the loo 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 bike.

The Mainichi Shimbun newspaper said that 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.

Ironically, moments before the fatal stabbing, the 41 year old had shared advice at a public event on how to deal with online disputes.

However Matsumoto was having nothing of that. He had posted messages containing personal abuse directed at Okamoto and other commenters on the blog. The Mainichi quoted a source as saying that Okamoto “had got into trouble before with internet users over the blog's content”?

In a message purportedly written immediately after the stabbing, Matsumoto said he had continued to abuse Okamoto by opening a new account every time his existing account was deleted.

He added: “I am going to go now to my neighborhood police box to voluntarily surrender and take responsibility for my actions.”

Matsumoto, 42, reportedly confessed to stabbing Okamoto, telling police he had grown to “hate” the celebrity blogger and wanted to kill him.

Okamoto worked for an IT security consulting firm and made regular TV appearances.

 Online personalities and journalists are often victims of online abuse in Japan, where attempts are being made to crack down on hate speech.