The motive behind an alleged arson attack on a studio of Kyoto Animation Co. in western Japan, which killed 33 people a day earlier, may have been the theft of ideas, sources said Friday.

Local media quoting investigative sources, said that a 41-year-old man apprehended over the alleged arson attack told police he started the fire at the three-story studio because the company "stole a novel."

More than 30 fire engines had to be deployed to the scene to deal with the inferno that started at around 10:30 a.m. on Thursday and claimed the lives of 33 people.

Local police and investigators said the suspect, identified by his driver's license, admitted on his way to hospital that he spread a flammable liquid, possibly gasoline, around the building before setting it on fire.

The suspect is believed to be a resident of Saitama Prefecture near Tokyo and is currently being treated in hospital for injuries he sustained in the fire.

He will be interrogated by the police once he has recovered, local investigators said.

According to police accounts, witnesses at the scene said the suspect was yelling "Die" as he started the deadly fire at the animation studio on Thursday.

A number of knives and knife-like objects were also found at the scene, although investigators have yet to determine if they belong to the suspect.

Kyoto Animation Co. runs studios in Kyoto and nearby Uji, where the company is headquartered.

Founded in 1981, the company is well known for its animations released in the 2000s that were popular with younger generations.

The firm also produces related animation artifacts and runs training programs for animators.