The cause of the blaze in Kolomna was not immediately known, the Investigative Committee said.
"Tonight, the investigative authorities received information that the bodies of five people -- four men and a woman -- were found after the fire was extinguished in the nine-story building," the committee said in a written statement.
RIA Novosti said the blaze was the latest in a rash of multi-fatality fires in the nation. Most have been traced to careless smoking and lax enforcement of safety rules during construction work.
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