A suspect detained after Thursday’s arson incident in Japan’s Kyoto city believed that the studio he allegedly set on fire had stolen his idea for a novel, Kyodo News reported, quoting police. The man confessed to using petrol to start the fire at the production studio office.

The fire killed 33 people and over 30 were injured. The accused, identified as Shinji Aoba, was caught soon after the fire broke out in the city’s Fushimi Ward. “I did it,” the 41-year-old told police when he was detained.

“[He] seemed to be discontented, he seemed to get angry, shouting something about how he had been plagiarised,” Reuters quoted an eyewitness, who saw Aoba being detained, as saying.

While the man’s driver’s licence showed that he was a resident of Saitama city near Tokyo, police said he had no fixed address, public broadcaster NHK reported. Police also suspected that petrol cans, kitchen knives, and a hammer found at the scene may belong to Aoba.

The accused is currently receiving treatment at a hospital for injuries to his face, chest, other parts of the body.

Crowds gathered at the site on Friday to pray and pay their respects after the incident. Locals were seen bowing or kneeling as some placed flowers in front of the building, The Washington Post reported.

Around 70 people were believed to have been working in the building when the fire broke out. The bodies of 11 people were found on the second floor of the structure, and four on the stairs. Prime Minister Shinzo Abe on Thursday said the incident was “too appalling for words” and offered condolences.