This photo taken on April 18, 2023 shows Beijing Changfeng Hospital where a fire broke out in Fengtai District of Beijing, capital of China. (PHOTO / XINHUA)

BEIJING – Twelve people, including the hospital chief, have been detained after the Beijing Changfeng Hospital fire that had left 29 dead as of Wednesday morning, according to a press conference.

The fire broke out Tuesday afternoon and was extinguished within an hour. The dead included 26 patients, one family member of a patient, one hospital caregiver and one nurse.

As of 6 am Wednesday, 39 others injured in the fire were being treated in other hospitals, according to Li Ang, deputy director of the Beijing Municipal Health Commission

As of 6 am Wednesday, 39 others injured in the fire were being treated in other hospitals, according to Li Ang, deputy director of the Beijing Municipal Health Commission.

According to the preliminary investigation, the fire was caused by sparks from a construction project that ignited volatiles produced by combustible paint.

Further investigation into the cause of the accident is underway.

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The fire was extinguished at around 1:33 pm on Tuesday, and the rescue operation lasted until 3:30 pm on the same day.

Top officials in Beijing demanded a thorough citywide check to completely eliminate potential security risks following the accident, Beijing Daily reported.

"We will carry out the inspection in an orderly manner, leaving no blind spots, in order to resolutely guard the security red line and protect the safety of people," Yin Li, secretary of the CPC Beijing Municipal Committee, said during a Tuesday night meeting held to arrange the follow-up work for fire relief.

The fire occurred at Beijing Changfeng Hospital in Fengtai district. A hospital admissions building caught fire at 12:57 pm on Tuesday, Beijing Daily reported.

Yin also ordered a quick investigation into the cause of the fire and those responsible will be held accountable in accordance with the law, he said.

Yin said the current urgent task is to spare no effort to treat the wounded.

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"The fire's consequence is painful, which rang an alarm bell and reminds us that the string in safety production must not be loosened and we cannot stop for a moment in eliminating fire hazards," Yin said.

He required to resolutely prevent the occurrence of severe accidents as a five-day May Day holiday draws near.

With Xinhua inputs