Russia has accused at least 555 Ukrainian citizens of treason, espionage, and related crimes since the start of the full-scale war, accounting for nearly 38% of all known defendants in such cases. Of those, 266 had been listed in Ukraine’s official register of missing persons, according to a study by the human rights group Pervy Otdel (lit. “Department One”) and Parubets Analytics, which based their findings on court records, law enforcement statements, media reports, information from lawyers and relatives, and open-source investigations.
People are entered into Ukraine’s missing-persons register as the result of reports from relatives or fellow service members. As of Aug. 8, 2026, 249 people covered by the study remained on the register, another 17 had previously been listed as missing but were later removed, seven were taken off the list after being released in prisoner exchanges, and one was officially declared dead.
Nearly 90% of the known disappearances (239 out of 266) occurred in Ukrainian territories that are under Russian military occupation. The most common last known locations were Melitopol, Nova Kakhovka, Kherson, Donetsk, Berdiansk, Enerhodar, Tokmak, Oleshky, and Skadovsk. Overall, 454 of the 555 people in the study — 81.8% — were first detained in Ukraine. Another 100 were detained within Russia’s internationally recognized borders, and one was taken into custody in Kazakhstan.
As of the time the study was completed, Russian courts had sentenced 402 Ukrainians on treason, espionage, and related charges . Courts in occupied Ukrainian territories handed down 241 of those sentences — 60.1%. Among individual courts, the Southern District Military Court in Rostov-on-Don issued the largest number of convictions, with 65.
Sentences are known in only 382 of the cases. Of those, seven received life terms, while the rest were sentenced to prison terms ranging from five years to 27 years and nine months. The median sentence was 14 years. In cases where treason or espionage charges were combined with terrorism or sabotage charges, the median sentence rose to 18 years.
In 323 cases, researchers from Pervy Otdel and Parubets Analytics were able to determine certain specifics of the accusations. Just over half of those cases — 176, or 54.5% — involved allegations of collecting and passing information to Ukraine about Russian troops, military equipment, and infrastructure. Another 37 people were accused of preparing or carrying out terrorist attacks, making assassination attempts, or successfully carrying out a killing. Additionally, 34 were accused of providing financial assistance to Ukraine, 15 of sabotage targeting transportation or infrastructure, and another 15 of serving in or attempting to join the Ukrainian armed forces or other Ukrainian formations.
As of the time of the study, 534 of the 555 people remained in custody, though researchers were able to determine the exact place of detention for only 360 of them. Of those whose locations were known, 236 were being held in facilities inside Russia and another 124 in pretrial detention centers and penal colonies in occupied Ukrainian territories. Researchers said Ukrainians have also been transferred to prisons in Siberia, the Russian Far East, and the Far North.
The report’s authors stressed that 555 is not a complete count. They estimated that the names of about 30% of defendants in such cases remain unknown due to the fact that proceedings are closed and court records often omit identifying information. The study’s data are current as of Aug. 8, 2026.
