MOSCOW - A big fire broke out in a mental hospital in Russia's Moscow region early Friday, killing at least 36 people, the Emergency Situations Ministry said.

Itar-Tass news agency reported that rescuers have found 36 bodies. The death toll could rise to 38 as only three out of the total 41 people in the hospital had escaped the fire, authorities said.

Firefighters try to cease the fire in a mental hospital where a fire broke out in Moscow's northern Dmitrovsky district, April 26, 2013. A big fire broke out in the mental hospital early Friday, killing at least 36 people, the Russian emergency department said. [Photo/Agencies]

The fire broke out at 2:23 am local time (2223 GMT Thursday) in a single-storeyed building of the mental hospital in Moscow's northern Dmitrovsky district. The fire has been brought under control.

The fire could have been caused by a short-circuit in the building, the police said, adding most of the peopled died in sleep inhaling the fumes.

Since the fire broke out at night, it was hard for those inside the hospital to escape and survive. A search and rescue operation was hindered due to heavy smoke around the building which was almost burnt down, local media reported.