KYIV  - Russia announced on Monday that it was engaged in a confrontation with infiltrators who crossed the border from Ukraine, marking one of the most significant attacks of this nature since the conflict began 15 months ago. The governor of Russia's Belgorod region, Vyacheslav Gladkov, stated that a Ukrainian "sabotage group" had entered Russian territory in the Graivoron district along the Ukraine border, and efforts were underway to fend off the incursion.

According to Ukrainian military intelligence, two Russian opposition groups, namely the Liberty of Russia Legion and the Russian Volunteer Corps, comprised of Russian citizens, were identified as responsible for the attack, as reported by the Ukrainian outlet Hromadske.

However, a Ukrainian presidential adviser emphasized on Twitter that the Kyiv government was not involved and was monitoring the situation. The Russian Volunteer Corps released video footage showcasing a fighter inspecting a captured armored vehicle, along with another video featuring fighters operating an armored vehicle on a rural road.

Videos circulating on social media platforms in Russia and Ukraine showed captured Russian servicemen and their identification documents.

The Kremlin confirmed that President Vladimir Putin was informed and efforts were underway to address the situation. Governor Gladkov of Belgorod reported injuries and damages to buildings, with a significant portion of the local population having evacuated.

A "counter-terrorist operation" was imposed, restricting movement and communication. Reports indicated fighting in three settlements, and disruptions in power and water supply were reported in several villages.

An armed group called the Liberty of Russia Legion claimed on Twitter that it had successfully taken control of the border town of Kozinka and was advancing towards Graivoron. This development drew comparisons to events in eastern Ukraine in 2014.

The Russian forces stated that the incursion was intended to divert attention from the situation in Bakhmut, a city in eastern Ukraine. Clashes continued along the frontline, with Bakhmut and Maryinka being the main focal points.

Russian forces conducted airstrikes and shelled several towns and villages in the area. The United Nations expressed concern over the lack of ship arrivals at Ukraine's Black Sea port of Pivdennyi (Yuzhny) under a wartime export agreement.