A third nurse managed to save two patients and they were the only three thought to have survived, the state news agency RIA Novosti reported, citing the Health Ministry.
Police said the fire, which broke out at about 2 a.m. local time (7 p.m. Eastern, 2300 GMT) in the one-story hospital in the Ramenskoye settlement, was caused by a short circuit, RIA Novosti reported.
A photograph on the website of the emergency services showed a building consumed by flames.
The emergency services also posted a list of the patients indicating they ranged in age from 20 to 76.
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