The bodies were discovered Friday on the bank of the Pakhra River just south of Moscow, the Russian Investigative Committee said in a statement on its website.
An examination of the remains indicates they were buried in the 1930s during the Joseph Stalin regime, RIA Novosti reported.
During Stalin's reign, it was common for people to be buried in mass graves throughout Moscow and St. Petersburg -- then Leningrad -- after they were rounded up and shot, the news service said.
Mass graves dating from the 1920s in Russia were the result of famines.
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