Two hacker groups, Kiberpartizany BY and Silent Crow, say they have breached Russia's Federal State Statistics Service (Rosstat) and obtained internal data that sheds new light on the human cost of the war in Ukraine. According to their analysis, between 393,000 and 450,000 Russian citizens have been killed since the full-scale invasion began in February 2022.
The groups claim to have exfiltrated roughly 23 terabytes of data, including demographic records, economic statistics, and internal documents. Using this material, they have produced their own casualty estimates, which are notably higher than most previously published figures.
Divergent counting methods
Kiberpartizany BY, a Belarusian group, counted deaths where military action or its direct consequences were listed as the cause. As of 27 August 2026, they tally at least 393,881 fatalities. Silent Crow, on the other hand, includes additional categories: non-combat losses among military personnel, deaths attributed to terrorist acts, and deaths of individuals registered in Russia who died in occupied territories or in Ukraine where the exact cause was not established. Their estimate reaches 450,100.
The discrepancy highlights the difficulty of measuring war losses in a country that has stopped publishing official casualty data. Russia has not released official figures since September 2022, and from 2024 Rosstat ceased publishing annual cause-of-death statistics, making independent assessment even harder.
Independent researchers have long relied on alternative sources. The BBC Russian Service and Mediazona maintain a named list of fallen servicemen, which contained around 286,000 names as of 8 November. However, this list is known to be incomplete, especially for recent months. A joint study by Meduza and Mediazona, based on inheritance registry data, estimated roughly 350,000 deaths by the end of 2025.
The hackers' figures are broadly consistent with these earlier estimates, lending some credibility to their claims. Yet journalists at Meduza and Mediazona, who have gained access to the leaked data, caution that authenticity and completeness still need to be verified. They are also checking for possible deliberate falsification.
Medical documents often do not reflect the true circumstances of death, and Rosstat's databases do not include up-to-date information on missing persons, who may only be declared dead after a long delay. Thus, even internal state statistics may not provide a definitive count.
The war's demographic impact extends far beyond the battlefield. Russian strikes have cut power for 850,000 Ukrainians as winter approaches, and overnight attacks on Kyiv have wounded civilians and damaged infrastructure. These attacks underscore the ongoing toll on Ukraine's civilian population, even as the focus remains on military losses.
European governments are closely watching these developments. Poland has urged Europe not to sideline Eastern security in any future negotiations, and the EU is struggling to bar Russian soldiers from Schengen entry. The human cost of the war is a central issue for the continent's security and demographic future.
While the leaked data offers a rare glimpse into Russia's internal records, experts warn that the true number of deaths may be even higher. The war continues to exact a heavy price, and independent verification remains essential.
