During the summer and autumn of 2025, Ukrainian forces reported that Russian troops had crossed the Jerebets River, a key waterway in eastern Ukraine. This movement allowed Russian forces to advance 17 to 20 kilometers toward the town of Sviatohirsk. Such a gain could have had major implications, as it might have led to the capture of Lyman, a strategic town that serves as a crucial logistics hub. If Lyman had fallen, it would have cut off vital supply lines, potentially disrupting Ukrainian operations in the south, particularly near the cities of Sloviansk and Kramatorsk. According to the Ukrainian information program TSN, the Russian advance created a "salient," or a bulge in the front line, which gave them the ability to press on Lyman from the north and increase their area of infiltration. This maneuver would have allowed Russian forces to apply pressure from multiple directions and complicate Ukrainian defensive efforts. However, by the end of 2025 and into 2026, Ukrainian forces reportedly held their ground against the Russian military, according to the news journal NV. Information about the conflict was tightly controlled, with both sides maintaining strict secrecy about their military actions. After successfully resisting the Russian advance, Ukrainian troops launched a counteroffensive that began in the spring of 2026. This operation was conducted under extremely tight security measures. The counterattack was carried out under an "Opsec" regime, short for operations security, which is a set of procedures designed to prevent the leakage of sensitive military information. The Ukrainian general staff imposed this strict secrecy to ensure that enemy forces could not anticipate or counteract the movements of Ukrainian troops. The BBC reported that this level of secrecy was crucial in the success of the counteroffensive, allowing Ukrainian forces to regain the initiative in the region.