Gas from above: How UAVs are bringing chemical warfare back to the battlefield in Ukraine

(Ukraine Ministry of Defense)

By Patrick Senft • Jul 23, 2026

Since Russia’s full-scale invasion of Ukraine on February 24, 2022, unmanned aerial vehicles (UAVs) have revolutionized modern warfare. These small consumer-grade and home-made drones have been adapted to drop munitions, crash into targets, or supply cut-off units. Simultaneously, the war has also been shaped by significant trench warfare when opposing sides face each other from well-protected positions, and the frontline moves relatively little. In combination, both these developments have given rise to the use of UAVs to deliver chemical munitions on the battlefield as both sides struggle to dislodge entrenched enemy units. Notably, since the early 2000s, various defense contractors have worked on delivering irritant agents via drones for domestic riot control, and police forces in India and Israel have been documented using such UAVs to disperse protestors. However, the war in Ukraine appears to be the first time UAVs have been used to deliver chemical agents as weapons on the battlefield at a significant scale.

This article examines the role of drones in deploying chemical munitions in Ukraine, drawing on open-source images and Telegram posts from military bloggers as well as publicly available sources. The phenomenon is underreported but poses significant legal, ethical, and military challenges. While these chemical agents are often classified as less-lethal munitions, commonly known as tear gas and riot control agents, their use raises the specter of escalating brutality in the war in Ukraine. Importantly, the Chemical Weapons Convention (CWC), to which both Russia and Ukraine are States Parties, specifically outlaws the use of less-lethal chemical agents on the battlefield, while permitting their use for domestic riot control purposes.

Once almost exclusively used for reconnaissance, small commercial off-the-shelf (COTS) and DIY/home-built drones have quickly evolved into one of the most versatile strike platforms in modern conflicts. By 2014, COTS and custom-built drones – mostly small quadcopter-type multicopter UAVs – had been modified by combatants in Ukraine to drop munitions and accurately hit targets on the ground. The relatively low cost and easy availability of COTS and DIY drones have allowed even small units to use UAVs for precise strikes and by now, UAVs have fundamentally changed the face of warfare in Ukraine.