"One nurse died trying to save the patients. Right now 35 people are reported missing," said a statement from the Investigative Committee, a Russian law enforcement body that probes major cases.
The fire, which according to preliminary information was sparked yesterday by a patient smoking in bed, quickly spread through the wooden structure housing at the all-male facility in Luka village in the region of Novgorod.
Around 60 patients and personnel were believed to be inside the hospital when it caught fire and around 20 were evacuated, the committee said.