A 31-year-old man indicted for remotely operating other people's personal computers to issue a bomb threat, and threatening other violent attacks in 2012, was released on bail Wednesday following 13 months in detention.

After initially approving bail for Yusuke Katayama on Tuesday, the Tokyo High Court suspended the decision in the face of a complaint filed by prosecutors. But the court decided Wednesday to release him, as it found the complaint was lodged by a prosecutor not authorized to do so.

After the release, Katayama told reporters: "I am innocent. My arrest was a bolt from the blue. I was also a victim of remote control."

The prosecutors maintain that Katayama, who has been in custody for about 13 months since his arrest in February last year, used Internet message boards to infect PCs with viruses enabling him to control them remotely and send email threats, including a bomb threat that forced a New York-bound Japan Airlines flight to return to Narita airport.