Police investigators say the arsonist of a Kyoto Animation studio last year has told them that he had thought his attack had left only a couple of people dead.

Aoba Shinji was arrested on arson and murder charges on Wednesday, ten months after he poured gasoline in the studio and set it on fire last July. His act killed 36 studio employees and seriously injured 33 people.

Investigators say they told him about the number of fatalities for the first time when he was arrested in his hospital room. Then, he said he never thought so many people had died, and imagined the number of fatalities might be about two.

However, Aoba also told police that he thought he would be able to kill many people with gasoline.

Police investigators say he is responding to police questioning calmly, but has so far not expressed remorse or given any apology.

Aoba himself suffered extensive burns after setting the gasoline on fire. He is still unable to eat or walk by himself.

Following the arson attack, police found six kitchen knives left lying near the studio. Aoba has told police that he had brought the knives from his home in Saitama and initially planned to use them in attacking people inside the studio.