The Institute for the Study of War has reported new evidence that Russian commanders are systematically ordering the execution of Ukrainian civilians, marking a further escalation in Moscow's violations of international law.

According to ISW's Saturday assessment, Russian troops from the 122nd Motorized Rifle Regiment stated that their commander instructed them to dress in civilian clothing — an act of perfidy under the Geneva Conventions—and execute all Ukrainian men encountered in the embattled Kupyansk sector under age 45.

ISW analysts also confirmed geolocated footage from Tuesday showing Russian troops operating in the Lyman area while disguised in civilian attire, further corroborating a deliberate effort to blur the line between combatants and noncombatants.

Such tactics, ISW notes, reflect a "systematization of deliberate war crimes" across Russian units rather than isolated battlefield atrocities.

The allegations fit a long-established pattern of Russian brutality against Ukrainian civilians since the invasion of February 2022.

The massacre in Bucha, uncovered after Russian forces withdrew from Kyiv in the spring of 2022, revealed mass graves and bodies of civilians with hands tied, shot execution-style. Similar evidence of summary executions, torture, and sexual violence has been documented in Irpin, Mariupol, Izyum, and Kherson.

Investigations by the United Nations, Human Rights Watch, and Amnesty International have confirmed widespread violations, including indiscriminate shelling of residential areas, deportations of Ukrainian children to Russia, and the targeting of hospitals and schools.

The attacks have been repeatedly documented as well. Under Article 37 of Additional Protocol I to the Geneva Conventions, perfidy constitutes a grave breach of international law and is prosecutable as a war crime.

These latest revelations are likely to intensify calls for accountability at the highest levels of the Russian government. In March 2023, the International Criminal Court issued an arrest warrant for Russian President Vladimir Putin, charging him with the unlawful deportation and transfer of Ukrainian children to Russia.

The warrant marked the first time a sitting leader of a U.N. Security Council permanent member was indicted by the ICC.

The Kupyansk area, located in the Kharkiv region, has been a major flashpoint as Russian forces attempt to regain territory lost during Ukraine's counteroffensive in late 2022.

ISW's findings suggest that Russian commanders, facing mounting battlefield pressure, are resorting to increasingly lawless tactics to intimidate local populations and undermine resistance.

"This is not random violence," ISW analysts concluded. "It is a deliberate policy ordered by Russian commanders to spread terror and suppress Ukrainian civilian morale."

As the war drags into its fourth year, the ISW report underscores that Russia's battlefield strategy continues to rely on war crimes as an instrument of warfare. For Ukraine and its allies, the revelations are a grim reminder that justice and accountability remain as critical as military support in the effort to repel Moscow's aggression.