Rescue teams have discovered ten more bodies when searching through the anime studio building in Kyoto, where a terrible fire erupted, APA reports citing NHK TV channel.
Medical services earlier confirmed deaths of thirteen people. Thirty-five more have been hospitalized.
At least 10 people have died in a suspected arson attack at an animation studio in Kyoto, Japan, local emergency officials have said, ONA reports citing BBC.
Local media quoted police as saying a man broke into the Kyoto Animation Co studio on Thursday and threw an unidentified liquid, starting a fire.
Dozens of people are also reported injured.
The suspect, who has not been named, has been detained and was taken to hospital with injuries.
"A man threw a liquid and set fire to it," a Kyoto prefectural police spokesman told news agency AFP. No other details of the suspect or possible motives were given.
The fire broke out at the three-storey building at around 10:30 am (01:35 GMT) on Thursday.
People near the site said they heard a series of explosions and later saw people carried out in blankets.
"A person with singed hair was lying down and there were bloody footprints," a 59-year-old woman living nearby told news agency Kyodo.
Another witness said he saw "red flames flaring".
Kyoto Animation, known as KyoAni, produces popular animation shows including "K-On" and "The Melancholy of Haruhi Suzumiya".
On social media, many fans have been expressing their shock and posting pictures of their favorite KyoAni shows.