The Supreme Court on Friday backed a district court's approval of the detention of the suspect in the deadly arson attack on Kyoto Animation Co. last year.
The top court's Third Petty Bench, under Justice Katsuya Uga, dismissed a lawyer's special appeal against the Kyoto District Court's decision to let public investigators detain Shinji Aoba, 42, until Friday.
On the same day, the Kyoto court approved the extension of his detention until June 15.
The Kyoto Prefectural Police served an arrest warrant to Aoba on May 27 on charges of setting fire to the No. 1 studio of the company, also known as KyoAni, in the city of Kyoto and murdering 36 people there, judging that Aoba, who was severely burned in the attack, had recovered enough to handle detention.
The Kyoto District Court, in rejecting the lawyer's quasi-appeal, said there are fears the suspect may run away or destroy evidence through the help of visitors because his condition is improving.
The district court set Tuesday as the date for disclosing the grounds for Aoba's detention. The disclosure will be made in an open court but it is uncertain whether the suspect will appear.
The suspect, who is still bedridden, is being held at the Osaka Detention House.