Anti-Kremlin hacking groups say Russia’s civil registries recorded at least 400,000 combat deaths in Ukraine, a statistic that Moscow has declined to disclose since September 2022.
The pro-opposition Belarusian group Cyber Partisans and the Ukrainian group Silent Crow said they obtained the data from 11 million death certificates and other records held by Rosstat, Russia’s official statistics agency.
Their findings say that 356,056 Russians were killed with “operations of war” as the cause of death, along with another 57,100 people marked as having died by other war-related causes or a “terrorist act.”
Another 36,949 deaths were listed with unclear or non-combat causes of death, the groups added.
Russia’s combat losses are likely far higher, Silent Crow said, as the tally doesn’t include statistics on the missing, wounded, or deaths of foreign mercenaries.
Rosstat did not immediately respond to a request for comment sent outside regular business hours.
The federal agency, which publishes a wide array of data but has withheld war mortality records, said in early November that it had been the target of a coordinated cyberattack campaign. Cyber Partisans and Silent Crow had claimed responsibility for the attacks, broadcasting messages on the agency’s website and online portals.
While both groups said they stole 23 terabytes of data, Rosstat denied that any data was leaked.
The hackers’ findings loosely align with other third-party gauges of Russian war losses.
A top British defense official estimated in September that nearly 500,000 Russian troops have been killed since the start of the full-scale invasion. Meanwhile, NATO’s former Supreme Allied Commander in Europe, US Ret. Gen. Chris Cavoli, said in July that roughly 450,000 Russian troops have been killed.
A more widely cited figure is the number of wounded and killed combined, which Ukraine says has eclipsed 1.6 million people, while Western think tanks estimate it hovers between 1.2 million and 1.4 million.
More details on Russian deaths
Cyber Partisans and Silent Crow also published data analysis on where the deceased Russians hailed from, as well as where they died.
The Volga region — one of Russia’s most populous and ethnically diverse heartland areas — accounted for 21.7% of deaths, taking the top spot, per the two groups.
Roughly 3% of the deaths were from Moscow Oblast, one of the highest shares among individual oblasts, though behind a few such as Rostov and Krasnodar Krai.
Data on the location of death was far more varied. The two groups said the stolen registries show that 54.9% of these soldiers were killed in Donetsk, while the next spot was Luhansk, which accounted for 8.3% of the deaths.
About 17% of the death registries listed unknown locations, per the two groups.
They added that the pace of Russian deaths recorded had risen by a factor of 1.26 over the past year, with each year of the war recording far more deaths than the previous.
There were 18,877 war-related death records in 2022, 42,365 in 2023, 109,683 in 2024, and 182,264 in 2025, the groups said.
About 99.4% of the deceased were men, with the most common age range being 35-44, accounting for 135,741 deaths. Nearly 40,000 Russians aged 18 to 24 were recorded as killed, per the groups.
Cyber Partisans and Silent Crow said the records show that war has become the fourth-most common cause of death in Russia.
