Military occupation by Russia
On 24 February 2022, the Russian military invaded Ukraine and began capturing and occupying parts of the Sumy Oblast. The capital of the oblast, Sumy, was never captured by Russian forces, however, other cites were captured including Konotop and Trostianets.
On 4 April 2022, Governor of Sumy Oblast Dmytro Zhyvytskyi stated that Russian troops no longer occupied any towns or villages in Sumy Oblast and had mostly withdrawn, while Ukrainian troops were working to push out the remaining units. Three days later, he said that all Russian troops had left the region, but it was still unsafe due to rigged explosives and other ammunition Russian troops had left behind. 
Occupation.
Konotop.
On 25 February, Russian forces captured the city of Konotop, from the Russian border.
On 2 March, Artem Seminikhin, the mayor of Konotop, stated that Russian forces in the city warned him that they would shell the city if the residents resisted them. Russian vehicles, deployed outside the City Council, were surrounded by locals. Seminikhin asked the residents of the city whether they wanted to fight or surrender, whereupon the residents "overwhelmingly" refused to surrender. Later in the day, city authorities negotiated with Russian forces, with talks lasting 12 minutes. An agreement was reached under which Russian forces accepted not to change the city's government, deploy troops in the city, obstruct transportation, or remove the Ukrainian flag. In return, the city officials agreed that the residents would not attack Russian forces.
On 7 March, the Ukrainian General Staff assessed that Russian forces at Konotop had taken 50 percent losses and were forced to regroup and resupply. On 15 March, Ukrainian and Russian forces agreed to open a humanitarian corridor to evacuate citizens from Konotop. On 28 March, Russian forces destroyed a bridge in Konotop.
On 2 April, it was reported that the Russian army maintained a corridor in Konotop Raion through which equipment from Kyiv and Chernihiv could be withdrawn to Russia. On 3 April, Ukrainian MP Olexander Kachura stated on Twitter that all Russian forces had left Konotop Raion. On 4 April 2022 Sumy Oblast's Governor Dmytro Zhyvytskyi stated that Russian troops no longer occupied any towns or villages in Sumy Oblast and had mostly withdrawn, while Ukrainian troops were working to push out the remaining units.
On 5 April, Governor Zhyvytsky stated that the bodies of at least three tortured civilians had been found in the Konotop Raion.
Romny Raion.
On the evening of February 24, the first day of the Russian invasion, two convoys of Russian soldiers coming from the cities of Nedryhailiv and Konotop (east and north of Romny, respectively) made their way in the direction of Romny. Between February 26 and 27, more Russian vehicles headed towards Romny from Krasnopillia, bypassing Sumy. The second convoy was bombed by Ukrainian forces before it reached Romny. On February 28, Russian forces attacked the Romny Correctional Colony. Meanwhile that same day, Russian forces crushed a civilian in the village of Pohozha Krynytsia when he attempted to use his car to block Russian tanks passing through.
On the first day of March, Russian forces captured the villages of Bilovods'ke and Bobryk, just south of Romny, which had been contested in previous days. On March 4, after negotiations with Russia and Ukraine, Romny was selected as a humanitarian corridor for civilians fleeing Sumy, Kharkiv, and Chernihiv oblasts. That same day, civilians from the village of Spartak attempted to block Russian vehicles passing from Nedryhailiv to Romny. They succeeded in blocking the road, although an ensuing attack by the Russians resulted in one civilian dying. Later that evening on March 4, Russian forces blocked the road from Lypova Dolyna towards Romny and Bilovod'ske, in southern Romny Raion, while the highway between Nedryhailiv and Romny was still under Ukrainian control. During the night between March 4 and 5, Russian soldiers destroyed a poultry farm, killed around 100,000 poultry and causing an estimated one million hryvnias worth of damage. 
On March 5, three out of four hostages who were taken by Russian troops were released, according to the head of Romny Raion, Denys Vashchenko. That same day, Russian soldiers standing on the road fired at Ukrainian TDF troops at a gas station, leaving one Ukrainian soldier killed and two wounded. On the evening of March 5, Russian soldiers fired at two cars traveling from Sumy to Romny, in the village of Pustovyitivka. 3 civilians were wounded, and one civilian was killed in the shooting. Later that evening, in the village of Skrypali in Romny raion, Ukrainian forces destroyed a Russian column, and killed an unspecified number of soldiers. In the evening between March 5 and 6, shots were fired in Pustoviitivka and Romny, with no injuries. The shooting in Romny, however, knocked out electricity for parts of the town.
On March 11, Vashchenko reported that Ukrainian forces unblocked the road between Romny and Lokhvytsia, allowing civilians to flee southwards. That morning near Romny, police and Ukrainian TDF discovered and detained 29 Russian soldiers in a field, all of whom claimed to be lost. The next day on March 12, green corridors were established in Sumy Oblast, where civilians from Sumy, Trostianets, Konotop, Lebedyn, Velyka Pysarivka, and Krasnopillia could flee towards Poltava Oblast. Humanitarian corridors restarted again on March 18. The Ukrainian General Staff reported on March 19 that the 1st Guards Tank Army of Russia began to concentrate efforts on surrounding Sumy, while also attempting offensives in Trostianets, Pryluky, and Romny, although these offensives did not succeed.
Boromlia.
According to locals, forces of the Donetsk People's Republic entered the village of Boromlia on the morning of 24 February.
Boromlia was struck by Russian airstrikes on 3 and 5 March 2022. According to residents, there was no Ukrainian military presence in Boromlia at the time, and the airstrikes caused extensive damage to civilian infrastructure: towns, shops, and a school.
The Russian military entered the village after the strikes, and Boromlia reportedly came under Russian occupation on 9 March. Due to the village's location on a highway, Russian columns frequently passed through it. According to locals, over 500 Russian military vehicles were in the village, and occupation forces consisted of Russians, Buryats, Chechens, and mostly, the forces of the Donetsk People's Republic.
Instances of torture, robbery, and abduction of local residents by Russian forces were reported during the occupation of Boromlia. According to Vasyl Romanika, head of the village administration, four people were tortured and killed during the occupation. Local officials claimed that a man was tortured and robbed in the village on 14 March.
The occupation of Boromlia ended on 26 March; Russian forces left during the night, and Ukrainian forces entered in the afternoon.
Trostianets.
As part of an offensive towards Kyiv, columns of tanks from the Russian 4th Guards Tank Division first passed through Trostianets on 24 February, with no real plans of occupying the city. However, the offensive quickly began to stall due to Ukrainian resistance west and southwest of Trostianets, and the detonation of a bridge south of the city. As a result, Trostianets, which was first envisioned as "little more than a speed bump" in Russian plans to swiftly take Kyiv, was occupied by a garrison of Russian troops on 1 March.
About a dozen checkpoints were established in and around the city. The main train station served as the Russian headquarters, and the police station and airfield also came under occupation. The number of Russian troops occupying Trostianets has been variously estimated between 300 and 800. Separatist militiamen from Donetsk and Luhansk arrived in the city following a mid-March troop rotation, and the presence of contingents of Buryat and South Ossetian fighters has also been reported. Units of the elite 4th Guards Tank Division, including the 12th and 13th Guards Tank Regiments, are reported to have been among the occupying forces.
During the occupation, Ukrainian police officers remained in the city incognito, supporting both local civilians and partisan forces operating in the area. The town's mayor, Yuriy Bova, hid in nearby villages, receiving some criticism for his decision not to stay in town, but continued to coordinate Ukrainian resistance, including shelling of Russian positions.
The Russian occupying force allegedly engaged in widespread looting, and "Guardian" journalists found evidence of torture and summary executions in the city. Residents of Trostianets during the occupation stated that people were shot in the streets. Unless neighbors or other civilians carried in the bodies of the dead, they would be left in the streets. These included the bodies of dead Russian troops, who were left there following the Russian retreat. Bova stated that at least 50 civilians were killed under Russian occupation. According to residents, two civilians were also killed in the neighboring village of Bilka, Okhtyrka Raion, which the Russians occupied on 2 March. 
Zhyvytskyi stated that Russian troops in Trostianets laid mines everywhere, including the town cemetery. After the Russian withdrawal, seven civilians were killed and at least two wounded due to traps laid by Russian soldiers across the town.
Ukrainian counterattack.
A Ukrainian counteroffensive recaptured the city on 26 March. During the fighting, the town's hospital was shelled, with residents blaming Russian forces. After combat and shelling around the outskirts of the city, Russian troops largely withdrew overnight before the arrival of Ukrainian forces. An AFP report recorded "a dozen" destroyed or damaged tanks and armored vehicles. The "New York Times" reported that food had grown scarce by the time the city was recaptured by Ukraine.
Sumy Raion.
Malyi Vystorop.
The village of Malyi Vystorop was occupied on 17 March. Russian forces took up residence in the village's vocational college, which they looted, according to its employees. When Russian forces left on 25 March, they fired reportedly on the college from tanks.
Velykyi Bobryk.
The village of Velykyi Bobryk came under Russian occupation on 17 March. Russian troops occupied a school building, and a local café served as headquarters. Locals accuse the Russian forces of looting shops, occupying and looting civilian homes, beating and torturing civilians, shooting indiscriminately, firing on civilian houses with BMPs, and abducting two civilian residents. The Russians left Velykyi Bobryk during the early morning hours of 26 March.
Steblianky.
The village of Steblianky came under Russian occupation on 19 March. Locals claim that Russian forces broke into unoccupied homes and looted them. The Ukrainian military forced the Russians out of the village on 26 March.
Humanitarian corridors.
"Green corridors" for evacuation functioned in Sumy Oblast on 12 March. People could go from Sumy, Trostianets, Konotop, Lebedyn, Velyka Pysarivka, and Krasnopillia through Romny to Poltava. According to the Head of the Military Administration Dmytro Zhyvytskyi, they finally managed to reach an agreement about Lebedyn, which had no electricity or communication at that point. At 9:00, a column of private transport and buses gathered at Lebedyn city council. The route was from Lebedyn via Shtepivka, Nedryhailiv, Korovyntsi, Romny, Andriyashivka, Lokhvytsia, Lubny and Poltava. Overall, 28 vehicles with 83 civilians and four buses with 52 civilians left Lebedyn.
On March 15, the humanitarian corridors worked in Sumy region on five routes - from Sumy, Trostianets, Lebedyn, Konotop and Shostka. The final destination of all routes was Lubny in Poltava region.
Humanitarian corridors worked in Sumy region on March 18. It was possible to leave the Velyka Pysarivka, Trostianets, Krasnopillia, Sumy, Lebedyn and Konotop communities. Lebedyn could leave on personal transport and buses from 9 am from the square near the city council. From the city the column moved through Shtepivka, Nedryhailiv, Korovyntsi, Romny, Andriiashivka and further to Poltava Oblast through Lokhvytsia to Lubny. The column was traditionally accompanied by representatives of the International Organization of the Red Cross. According to the regional military administration, as of 5:00 pm, 4 buses carrying 50 citizens had left Lebedyn.
References.
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