Japanese police on Wednesday formally arrested a man on suspicion of an arson attack on an animation studio in the city of Kyoto last year that left 36 people dead, according to the police spokesman.

“We arrested Shinji Aoba, 42, on suspicion of the murder of 36 people by setting fire” to an animation studio, a police spokesman told media.

The arrest came 10 months after the attack on the Kyoto Animation studio, which also injured dozens of people.

Aoba was arrested on suspicion of murder and arson among other crimes. The number of victims makes it one of Japan’s biggest ever murder cases.

Earlier, the police had planned to arrest Aoba, who is still largely bedridden, around January but arrangements were affected by the spread of the new coronavirus and his unstable health condition, according to investigative sources.

A motive for his alleged attack remains unclear, though he reportedly confessed to the arson.

Acording to reports, Aoba accused Kyoto Animation of plagiarising his work.

Aoba allegedly “broke into the studio, scattered gasoline on the ground floor, set fire to it and killed 36 people” — 14 men and 22 women, the police spokesman said.

He is also accused of attempted murder over the injuries of 34 people, and possessing knives on the street without legitimate reasons, in violation of Japan’s strict laws on weapons.

In response to Aoba’s arrest, Kyoto Animation said in a statement, “We have nothing to say to the suspect…Our fellow workers whose lives were lost will never come back and the wounds of our colleagues will never be healed.”

The company said it expects Aoba to face “maximum criminal responsibility,” according to the statement issued though the studio’s legal representative.

The incident sparked an outpouring of support from the industry and fans worldwide, including a viral fundraising campaign.

The fire gutted the three-storey building in the city of Kyoto that housed Kyoto Animation, which was behind famous anime television productions.

Kyoto Animation, known by its fans as KyoAni, is well-known both domestically and internationally for its role in producing popular TV anime series including “The Melancholy of Haruhi Suzumiya” and “K-ON!”

While many animation studios are based in Tokyo, the firm reportedly felt strongly about remaining in the ancient Japanese city of Kyoto.

(With inputs from agency)