Tokyo cat grasses up mystery hacker -

Japanese police had their claws out after trying to tail a hacker who used a cat as a key communications device.

Fur flew on Sunday when Inspector Knacker of the Japanese Yard fingered the collar of a man suspected of being behind a computer hacking campaign.

Crucial to the arrest was evidence gathered by interrogating the man's cat, which proved more fruitful than the "confessions" of four men the coppers had previously arrested - who were innocent.

According to the Sydney Morning Herald, the hacker, Yusuke Katayama, 30, liked evading the authorities with a series of cyber-riddles. He left a trail of clues that had the police stumped, as well as sending numerous threats from computers around the country - including against a school and a kindergarten attended by grandchildren of Emperor Akihito.

Cops, caught in a cat and mouse game with the hacker, had been unable to stop him. They then became embarrassed by a scandal over the case when it emerged that officers had extracted "confessions" from four people who had nothing to do with the threats.

Prosecutors claim that Katayama sent messages to newspapers and broadcasters claiming details of a computer virus used to dispatch the threats were strapped to a cat living on an island near Tokyo.

After cracking a set of riddles, police found the cat and removed a digital memory card from its collar which revealed a message saying "a past experience in a criminal case" had caused the hacker to act.

The card claimed that the case "changed" the anonymous hacker's life, and added that "no more messages will be sent".

This time, the hacker had made a mistake - in that he trusted the cat wouldn't snitch. Anyone who has owned a cat knows that they will sell their owner out in return for three square meals a day and a warm place by the fire.

After looking at the memory card and footage taken by security cameras, and giving the cat some of the finest salmon in Tokyo, the coppers had enough evidence to arrest Katayama. Police did not say if the cat had turned super-grass, but it looks like the cat had its paws all over the case.