A fire erupted overnight in a private illegal nursing home in the Siberian city of Kemerovo, killing 22 people, Russia's investigative committee said Saturday.
In a video released by the emergency services, a long row of emergency vehicles lined up outside the burning building, as firefighters tackled flames which sent plumes of smoke into the night sky.
Images released by emergency services showed the building later completely burned out.
Russia's investigative committee -- which investigates major crimes -- said it opened a probe into causing death by negligence.
"A fire broke out overnight in a private property used as a nursing home," the investigative committee said on Telegram, adding that "the death toll has risen to 22".
A previous statement on Telegram had called it an "illegal" home, but a later version edited the phrase out.
However a police source quoted by the Russian state-run news agency TASS also called the home illegal.
"Six more were injured, two of them were hospitalised and are in a serious condition with burns," the Telegram statement added.
An earlier statement from the emergency services reported 20 people had died.
The fire spread over 180 square metres in a two-storey wooden building, TASS reported.
Faulty stove
The committee said a 31-year-old man had been taken for questioning, who had "rented out a private property to people in (a) difficult situation."
"On the eve of the incident, the tenants informed the accused that the stove was faulty, but he did not take any action to repair the equipment," the investigative committee said.
"Inspections on the scene are ongoing," the committee said, adding that "witnesses are being questioned".
The committee published a video of one detainee with his face blurred.
The emergency services said the premise had been identified in 2021 and an inspection had been scheduled.
"On December 7, the inspector of the State Fire Supervision Service arrived at the facility for a check. The management of the shelter denied him access to the premise," the emergency services said on Telegram.
Regional governor Sergei Tsivilev instructed local authorities to "identify legal entities, entrepreneurs, citizen who provide social services for the elderly and disabled".
"When violations are identified, take comprehensive measures to eliminate them," he said in a statement on Telegram.
Earlier, Tsivilev said his administration would "inspect all institutions of this type, and as a priority, private ones... within a week."
Fire safety rules are often violated in Russia due to corruption as building permits are given by officials in exchange for bribes.
In 2018, a shopping centre fire in Kemerovo left at least 64 people dead, including 41 children.
Following that disaster, fire safety failings had been recorded at hundreds of commercial and cultural sites across Russia.