22 May On 22 May 2023, footage emerged on Russian
Telegram channels showing an apparent military raid on the Russian border checkpoint in the
Grayvoronsky District of Belgorod Oblast. He said there were explosions and drone attacks in the district. The
Freedom of Russia Legion and the
Russian Volunteer Corps claimed responsibility for the incursion, announcing that the two groups working together had taken control of the villages of
Kozinka, In this incursion participated the
Polish Volunteer Corps, a
Polish volunteer military unit created in mid-February of the same year. They would only confirm this on 4 June after posting images on Twitter proving their involvement; up until that point, there had been reports from Russian soldiers that some of the saboteurs spoke
Polish. The Russian Volunteer Corps posted photos of their fighters in front of road signs for the settlement of
Bezlyudovka in Belgorod Oblast, as well as and in neighboring
Bryansk Oblast. On the evening of 22 May, Gladkov also said that the Belgorod regional government officials, together with the
Ministry of Emergency Situations, was going from house to house in border villages to evacuate civilians, and that "most of the population" had been evacuated. According to Ukrainian officials, Russian forces began an emergency evacuation of
nuclear ammunition stockpiles from the nearby Belgorod-22 facility. The Belgorod-22 site is
Military Unit Number 25624 of the
12th Chief Directorate. Nuclear security expert at the
United Nations Institute for Disarmament Research, Pavel Podvig, was skeptical about the announcement of the movement of nuclear weapons, since such a maneuver could not go unnoticed by Western intelligence agencies. Despite the current status of the military unit to which the repository belongs, it would be impossible to establish the presence of nuclear weapons in it, Podvig said. The Rybar Telegram channel stated that nuclear weapons were not stored at this facility long before the raid.
23 May According to video reports, the
Federal Security Service (FSB) office in the city of Belgorod was struck in a drone attack, nearly away from the "combat zone". The Freedom of Russia Legion posted footage showing ongoing fighting. Later, during the night of the same day, the Ukrainian journalist
Andriy Tsaplienko posted a picture on his Telegram channel showing five allegedly Russian opposition soldiers in front of the entrance sign of , a village in
Kursk Oblast. It is unknown to which military unit these soldiers belonged and no official information was released about the incident.
Aftermath On 24 May, governor Gladkov announced that anti-government forces were no longer in the region. He also said that the following districts had been attacked during the incursion:
Borisovsky,
Volokonovsky,
Grayvoronsky,
Krasnoyaruzhsky,
Shebekinsky, and
Yakovlevsky. He later announced that Russian authorities had created seven territorial defense battalions for the defense of the Belgorod region in the future. The leader of the Russian Volunteer Corps,
Denis Kapustin (also Denis Nikitin or "White Rex"), said the group had left Russian territory after 24 hours, and that they were satisfied with the raid at a press conference given on Ukrainian territory. ==Second raid==