Ukraine’s overnight drone strike on Russia’s territory on 22-23 September may have contained something unprecedented — high-flying balloons, possibly armed with explosives of some kind.

Russian officials reported shooting down dozens of drones, but the Russian Ministry of Defense made no mention of balloons — or aerostats, per the more technical terminology.

The reports of aerostats drifting over Russia largely came from Russian Telegram channels, which warned of balloons containing explosive objects of unspecified nature.

Russian publication RBK cited unnamed Russian defense officials in claiming that a large number of balloons was observed during the attack, something they hadn’t previously seen Ukraine throw at them.

One Russian channel reported a balloon flying at an altitude of 10 kilometers, which is a typical cruising altitude for commercial airliners.

The attack reportedly forced flights to divert from Moscow’s Sheremetyevo airport.

Fixed-wing drones were reportedly sighted over Moscow during the attack, matching the profile of the UJ-22 Airborne bomber UAVs in use by Ukrainian forces.

Does Ukraine’s military use balloons as weapons?

While Ukraine made no mention of technology used in the strike, the country’s armed forces have access to tethered balloons that can serve as detectors and launch platforms for interceptor UAVs to strike down Russian attack drones.

Pictures from social media in March appear to show a balloon developed by the Ukrainian company Aero Bavovna carrying a fixed-wing drone under its translucent belly.

On its website, Aero Bavovna describes its aerostats as “accessible and versatile airborne platforms for communication and monitoring” that can provide “reliable control and security in any conditions for both mobile and stationary applications.”

The company says balloons can carry payloads including FPV repeaters, communicators, cameras, and electronic countermeasures, although it makes no mention of launch cradles for smaller drones.

In a recent interview with Euromaidan Press, Hudson Institute fellow Brigham McCown mentioned that tethered aerostatic drones can be useful devices for monitoring and detection thanks to their indefinite uptime.

The multi-kilometer heights balloons can reach may also put them out of range of many shorter-range countermeasures.