The governor of Siberian mining region Kemerovo Oblast has launched a region-wide inspection on all coal, ore, and open-pit mines as the death toll from the Listvyazhnaya mine gas explosion in Russia rises to 52, as of 16:45 local time.

In a statement, the regional government said the federal prosecutor would launch a safety assessment of all mines in the area; according to Reuters, three people have been arrested for suspected safety breaches at the mine.

The death toll of 52 includes six miners who went to the aid of others killed in the gas explosion, the regional government said.

Sergei Tsivilev, governor of the Kemerovo Oblast, said 11 miners are still in hospital - 10 with poisoning, one with a "traumatic brain injury."

"We will do our best to assist relatives and those who are being treated," Tsivilev said.

Furthermore, the site itself will not become safe for at least three days due to the low level of methane.

He explained that 257,000 cubic meters of the mine site would be isolated and filled with methane to stop another explosion.

"It is necessary for the methane level to rise above 20%, then the risk of an explosion will decrease," Tsivilev said.

"According to our forecast calculations, this is three days. After the expiration of this time, a decision will be made to carry out work at the mine."

In an update at 18:23 local time, the Investigative Committee of Russia has charged Sergei Makhrakov, director of the Listvyazhnaya mine in the Kemerovo Region, first deputy Andrei Molostov and site manager Sergei Gerasimenk with "death of two or more individuals through negligence."

Chief state inspectors of the Belov territorial department of the Siberian Department of Rostekhnadzor Sergei Vinokurov and Vyacheslav Semykin, have also been charged with causing death by negligence. 

"As a result of violations of industrial safety requirements of industrial facilities, allowed the mine director Mahrakov and his subordinates, there was a gas dynamic phenomenon and the subsequent smoke in the ventilation shaft area, which led to the death of workers who were in the mine," a statement from the Committee read. 

"Sergei Vinokurov and Vyacheslav Semykin improperly performed their job duties of supervising the industrial safety requirements at a hazardous production facility," it continued.

"The inspectors drew up acts of inspection of this drift without actually checking it."

The Committee concluded by saying the investigation was still ongoing.

Russian company SDS-UGOL, the owner of the mine, has not responded to requests for comment.