A computer expert on trial for sending violent threats from other people's hacked computers has admitted he's guilty, calling himself "a psychopath" in a surprise confession, his lawyer said Tuesday, potentially ending a case that had earlier seen police arrest the wrong suspects.

Former IT worker Yusuke Katayama, 32, was first arrested in February but insisted he was "utterly innocent." In a conversation with his lawyer on Tuesday morning, he delivered a full confession, saying he is capable of deception without feeling the slightest remorse, according to the attorney, Hiroshi Sato.

The Tokyo District Court later revoked Katayama's bail upon a request by the Tokyo District Public Prosecutor's Office. He was rearrested and held at the Tokyo Detention House.