OSAKA -- Mamoru Takuma, suspected of killing eight children in a June 8 stabbing spree at an Osaka school, will likely be indicted next month now that doctors have concluded he was mentally fit at the time of the attack, sources said Thursday.

Three psychiatrists concluded that Takuma, 37, was able to tell right from wrong and was perfectly mentally fit when he allegedly stormed the state-run Ikeda Elementary School in Osaka Prefecture, fatally stabbing the eight and injuring 13 other pupils and two teachers, the sources said.

The doctors have already notified prosecutors of their conclusion and are now compiling a report, the sources said.