A 27-year-old man in Osaka Prefecture has been charged with destroying stored data by using a computer virus that replaces victims' files with octopus or squid icons.
Masato Nakatsuji allegedly distributed the virus through a file-sharing program in May and destroyed the hard disk of a computer owned by a Hokkaido man who obtained the program a month later, according to the indictment filed Monday by the Tokyo District Public Prosecutor's Office.
Nakatsuji in 2008 became the first person in Japan to be arrested for creating a computer virus. He has been on probation after receiving a suspended two-year sentence for copyright infringement.
After arresting Nakatsuji earlier this month, police said he told them about 50,000 people were affected by the virus.