Workers rebuilding a 19th century Moscow house dug up the remains of nearly three dozen people and investigators were trying to determine their identities, a city police official said Thursday.
Police also found a rusted pistol in the estate where the remains of an estimated 34 people were found, said Moscow city police spokesman Yevgeny Gildeyev.
The property was owned by a famous czarist-era noble family, the Sheremyetevs.
Some of the remains, which were found in a basement of one of the estate's buildings, had gunshots to the skulls and appeared to date back to the 1930s, he said, and more could be found.
The Soviet Union in the 1930s experienced a wave of politically motivated killings and purges of the government and Communist Party orchestrated by Josef Stalin's secret police. The killings reached their apex in 1937 during what came to be known as the Great Terror.
An estimated 1.7 million people were arrested in 1937-38 by the security services alone, and at least 818,000 of them were shot, historians estimate.