He can’t get the women out of his mind.

A day after an apparent arson killed 33 people at an animation studio in the Japanese city of Kyoto, a neighbour, the 81-year-old Ken Okumura, remembered seeing several women jump from the building’s second floor. They were so badly burned that blood was coming from their noses, and all of their clothes but their underwear were gone.

“Just horrible,” Okumura said on Friday, as the smell of burning still hung in the humid air.

Much was still unknown about the Thursday fire, which appeared to be Japan’s worst mass killing in decades. The police identified Shinji Aoba, 41, as a suspect in the case, based on statements they said he made when he was apprehended. They said Aoba was being treated for severe burns and had not been arrested.

Japanese news reports, citing unnamed police sources, said the suspect had told the police that he started the fire because he believed the studio, Kyoto Animation, “stole a novel” from him.

NHK, the public broadcaster, reported that Aoba had served time in prison for robbery and that he was being treated for an unspecified mental illness. The report, which cited an unidentified source, said he lived in the city of Saitama, near Tokyo.

As of Friday, none of the names of the 33 people killed in the fire had been released. What was known was that almost two-thirds of them — 20 — were women.

That appears to reflect a trend in Japan’s animation industry, as well as the hiring practices at Kyoto Animation. There are about twice as many women as men among working animators in their 20s, according to Daisuke Okeda, an adviser to the Japan Animation Creators Association.

Male animators still lead the industry, and they outnumber women among animators over 35, Okeda said. But Kyoto Animation — known as KyoAni to its fans — is known for employing more women, particularly younger women.

More than half of the workers in the burned building were women, based on figures released by the Kyoto fire officials about the dead as well as the dozens of injured. On Friday, a man distraught about his 21-year-old granddaughter, who worked at Kyoto Animation, said he could not find her name on lists of people taken to local hospitals.