Cat cuffing: Japanese cops collar suspect for mass murder e-threat

Japanese cops have cuffed a suspect in a high-profile cyber threat and computer hacking case that had police examining a cat for clues at one stage of the investigation. Police said a memory stick found on a cat's collar led them to make the arrest.

However, a whopping four innocent people, including an anime director, have already been mistakenly arrested for the incidents to which the current suspect has been linked. The man denies any wrongdoing, and was reported by English-language Japanese newspaper Yomiuri Shimbun as protesting, "That's not true at all" during his arrest.

Yusuke Katayama, 30, from Tokyo, was nabbed on Sunday over alleged involvement in a trolling operation that involved posting threats to online message boards through hijacked computers. One of the messages threatened mass murder at a comic book convention while another warned of supposed plans to assault a school and kindergarten attended by Emperor Akihito’s grandchildren.

Four other people whose computers were hijacked were arrested between July and September last year before forensic examinations of their respective computers cleared all four of any wrongdoing. The Japan Daily reports that this proved hugely embarrassing for Japan’s National Police Agency, which was forced to admit it had obtained "confessions" from innocent parties.

Katayama is suspected of sending a message to reporters on 5 January claiming responsibility for the threats, which the missive had claimed were motivated by a desire to expose police incompetence. The email asked recipients to solve a puzzle stored in a memory card embedded in the collar of a stray cat, living on a small island called Enoshima.

Police duly discovered the memory card, which appeared to contain the source code for a computer virus and text that apparently described the perpetrator's motives. According to Yomiuri Shimbun the text read: "I found myself involved in a crime in the past. Even though I was innocent, it forced me to completely change my way of life." The report shows the suspect being led away by police.

Police claimed that CCTV footage showed Katayama approaching the cat and reportedly taking its picture the day before led to the arrest of the 30-year-old, UPI reports. ®