Smoke rises from a psychiatric hospital where at least 36 people are feared dead, with some killed in their beds by a blaze that started in the early hours of Friday.

Some were trapped behind barred windows while the collection of brick and wood huts north of Moscow burned.

An official said three staff and 38 patients were inside when the fire started.

Moscow's interim governor earlier said two patients made it out when a nurse helped them to safety.

Not all the window bars met regulations, he said, which may have prevented more escapes.

Authorities say the fire may have been caused by patients smoking or an electrical fault.

Fires at state institutions in Russia often cause casualties, raising questions about safety measures, conditions and escape routes.

They country also has a much higher per capita death rate from fires than Western nations, with 12,000 people killed in 2011.