Today, investigators revealed that the man told them he was aiming to imitate the deadly Kyoto animation arson attack that occurred in 2019.
Gasoline appeared to have been deliberately spilled in the hall outside the elevator on the third floor, leading investigators to believe it was an arson attack.
On 24 March, a man was arrested on suspicion of setting fire to a building in the city of Tokushima, where a Japanese idol group concert was taking place.
According to investigators, Okada purchased approximately 14 litres (3.7 gallons) of gasoline from a self-service gas station within the prefecture a few hours before the incident.