A drone flies over Kyiv during an attack on October 17, 2022, amid the Russian invasion of Ukraine.
Washington CNN  — 

Iran appears to be modifying the attack drones it’s providing to Russia so that the explosive warheads can inflict maximum damage on infrastructure targets inside Ukraine, according to a new investigative report obtained exclusively by CNN.

Iran has given Russia hundreds of drones to use in its war in Ukraine, many of which have targeted Ukraine’s power grid and energy facilities to devastating effect. The drone attacks, as well as barrages by Russian missiles, have left Ukrainian civilians across the country without heat, electricity or running water during the freezing winter months.

An unexploded warhead from an Iranian Shahed-131 drone found in the Southern Ukrainian region of Odesa in October 2022 was examined last month by the UK-based investigative organization Conflict Armament Research, along with the Ukrainian military. CAR provided its findings first to CNN.

The composition of the warhead helps explain how Russia’s onslaught on Ukrainian energy infrastructure over the last several months has proven so effective.