A murderous firebug torched a so-called ‘video hotel’ stocked with manga, dirty movies, and salarymen in Osaka, killing 15 patrons. These Japanese killing sprees just get more and more weird, don’t they? I’m sure if you set an American hotel on fire, all you’d destroy would be a bunch of Gideon Bibles and bedbugs.

Police identified the alleged arsonist as Kazuhiro Ogawa, who appears to have selected the location to inflict maximum loss of life: like so many of the “manga kissa” comic libraries and adult-video viewing parlours dotted around Japanese cities, the down-market Cats video house doubled as an ultra-cheap hotel and its 32 cramped cubicles were nearly always full.

The apparent use of fire to kill so many people has severely shaken Japan in what has already been an unsettling year of indiscriminate murders: seven people died in June when the central Tokyo shopping district of Akihabara was turned into a bloodbath by a lone knifeman.

Mr Ogawa allegedly set fire to a bag of newspapers in his room in the small hours of Wednesday morning. Investigators believe that he would have almost certainly known that most of the other rooms were occupied and that nearly all of the customers were fast asleep.