Russia attacked multiple oil and other facilities in Donetsk, controlling over a hundred buildings.

The General Staff of the Ukrainian military announced on the 21st that on the 20th and 21st in the early hours, the Ukrainian army launched remote strikes on oil terminals, railway facilities, and refineries in the Krasnodar Krai and the Rostov Oblast of Russia. The Russian Ministry of Defense also released a report on the same day, stating that on that day, Russian forces continued to attack the cities of Horlivka and Konstantinovka in the Donetsk region, seizing control of over a hundred buildings. The General Staff of the Ukrainian armed forces also reported on social media that Ukrainian forces attacked three railway bridges used by the Russian army to transport military supplies and personnel on the southern front. On the 20th, the Ukrainian army launched an attack on the Azov Oil Refinery, one of the largest refineries in Siberia. The Russian Ministry of Defense's report on social media on the 21st showed that the western group of Russian forces advanced in the northwestern part of Horlivka, "clearing" Ukrainian armed personnel from 53 buildings. The southern group of Russian forces on the same day attacked Konstantinovka and seized control of 104 buildings in the southwestern part of the city from the Ukrainian side.