Countdown to murder - the final posts

Sunday’s five-minute eruption of violence by a lone knifeman, in which seven people were stabbed to death beneath the neon lights of Tokyo’s Electric Town, may have been planned for months.

The selection of Akihabara — a district famed as the cradle of modern Japanese youth culture — appears to have been a central part of the killer’s scheme. And in plotting his spree, Tomohiro Kato appears to have chosen people he considered most like him: the obsessive geeks of a subculture known as otaku.

Friends of Mr Kato described him yesterday as a typical Akihabara type — a cartoonist of reasonable talent who would “lose himself for hours in cyberspace”. When he went to karaoke, he would select the theme tunes of TV animations; when it came to women he would declare that he was “only interested in two-dimensional girlfriends”.

Police investigating Japan’s worst killing rampage believe that the attacks were planned. In the days before the spree, Mr Kato made several visits to Akihabara to establish its suitability for his ambitions. “I knew there would be lots of people and I decided this some days ago,” he told police. Even as the minutes ticked down to the start of his rampage, he is believed to have recorded his thoughts on a blog through his mobile phone. The first comment, which appeared on the internet at 5.21am on the day of the violence, read: “I will kill people in Akihabara, have a vehicle crash and, if the vehicle becomes useless, I will use a knife.” After a running commentary that tracks his 100km (60-mile) drive from Susono, in the foothills of Mount Fuji, the messages end just minutes before the attacks. “It’s time; I’m going,” read the final comment.

Until this weekend, he appeared to have led the average life of a young Japanese man from a small, provincial town: a serious boy who graduated from a good local high school in the northern prefecture of Aomori, and headed south to work in a car-parts factory in Shizuoka. According to work colleagues, he would become deeply immersed in online forums.

He appears to have shared with tens of thousands of young Japanese men a passion for Akihabara and its maze of shops that helped to create Japan’s otaku stereotype. Originally, otaku referred to a sub-class of youth culture that encompassed manga comics, video games and animated pornography. More recently it has gone mainstream and financial analysts track the spending habits of its participants.

But on Sunday, the façade of normality around Mr Kato slipped. At about 8.45am he arrived at a colleague’s house to give him a bag of DVDs and video games, leaving with the message: “I’m going to deliver this truck to Akihabara. I’m going to stop there briefly and then I’m flying east.”

Three and a half hours later, Akihabara became a bloodbath. The victims included Katsuhiko Nakamura, a dentist who was having lunch with his wife and son, and Mai Muto, a student at Tokyo University of the Arts whose part-time job was to sell mobile phones from a booth on the crossroads where the killing took place.

The mainstream media have spent the past five years demonising the otaku phenomenon, and the horrors of the weekend will only heighten the suspicion and dislike of the geeks of Akihabara.

Sunday June 8: texts for a killing

05.21 Sleepy. Will drive into [the crowd] and, if the car becomes useless, I will use a knife.

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