Updated December 17, 2021, 12:38 p.m. ET

OSAKA, Japan – A fire that spread on Friday at a psychiatric clinic on the fourth floor of an eight-story building in downtown Osaka, western Japan, left 24 people dead in what police was investigating a possible case of arson and murder.

Police were looking for a man in his 50s to 60s who witnesses saw carrying a paper bag leaking unidentified liquid. He may have been among the 24 dead, or is one of three people who have been resuscitated and remain in serious conditions, or may have fled, a police investigator said on condition of anonymity because he did not was not allowed to speak to the media.

Firefighters who reached the building in Osaka’s main business, commerce and entertainment district of Kitashinchi found 27 people in cardiac arrest, Osaka Fire Chief Akira Kishimoto said.

A woman was conscious and shot through an aerial ladder from a sixth-floor window and was being treated in a hospital, he said. Later Friday, 24 people were pronounced dead, firefighters said.

In Japan, authorities usually describe people without vital signs as “shinpai teishi,” or in a state of cardiac and pulmonary arrest, and do not confirm deaths until they are pronounced in hospitals and the deaths. other necessary procedures are not performed.

Police and firefighters gather near the building in Osaka.

A doctor at one of the hospitals treating the victims said he believed many of them died after inhaling carbon monoxide because they had limited external injuries. Police said the cause of death could not be determined until the bodies were autopsied.

One of the clients said the clinic was popular and was always packed with 15-20 people waiting, especially on Fridays when special counseling and programs were available for those preparing to return to work after taking sick leave, NHK said.

Authorities are investigating the possibility that the smoke filled the ground so quickly that the victims did not have time to escape, Nippon Television said.

Hours later Friday night, crowds were still gathering outside the building to get a glimpse of the scene where firefighters and police were investigating.

“I haven’t heard of the cause but I’m shocked and wonder why anyone would do this,” said Yuji Uehara, who works for a financial firm. “I also offer my condolences to those who have passed away.”

The building houses the mental and internal medicine clinic, an English school and other businesses. Most of the victims are believed to be visitors to the clinic on the fourth floor, firefighters said.

First responders carry a stretcher after a deadly fire at an eight-story building in a major business, commerce and entertainment district in Osaka on Friday.

Yukie Nishizawa / Kyodo News via AP

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Kyodo news via AP

First responders carry a stretcher after a deadly fire at an eight-story building in a major business, commerce and entertainment district in Osaka on Friday.

Osaka Police said earlier they were working to determine whether the blaze was caused by arson. They then set up a team at the prefecture’s police headquarters, a sign that they strongly suspect arson and murder.

According to NHK, an outpatient at the clinic reception saw the man wanted by police. Another person nearby said the fire started shortly after placing the leaking bag next to a stove on the floor and kicking it, more of the liquid flowing out .

The clinic’s psychiatrist, Kotaro Nishizawa, could not be reached since the fire, NHK said. He quoted his father as saying the doctor had hinted at a problem at the clinic but did not give details.

Residents on other floors of the building were safely evacuated, firefighters said.

NHK cited a witness as saying he heard a woman’s voice coming from the fourth floor calling for help. Another witness told TV Asahi that he saw flames and smoke coming out of the windows on the fourth floor when he came out after hearing a commotion.

A total of 70 fire trucks were mobilized to tackle the blaze, which was completely extinguished more than six hours later, officials said.

In 2019, at Kyoto Animation studio, an attacker broke into the building and set it on fire, killing 36 people and injuring more than 30 others. The incident shocked Japan and sparked a wave of grief among anime fans around the world. In 2001, an intentionally set fire in Tokyo’s Kabukicho entertainment district killed 44 people – the worst case of arson in the country in modern times.

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