Ukrainian drone operators near Lyman destroyed four Russian tanks and seven infantry fighting vehicles before they could leave their dugouts.

The vehicles were invisible from the air—engines cold, camouflage intact. Thermal cameras couldn’t spot them. So the drone team listened instead.

“We know that Russians planned to attack our positions,” operator Kriegsforscher reported. His unit tracked the armor through radio signals, then sent in the drones.

The 20th and 25th Russian Armies are massing to push toward Sloviansk—one of Ukraine’s last free cities in Donetsk. The T0514 highway from Lyman leads straight there.

Ukraine is trying to blunt the offensive before it begins.