From 2016 until August 2021 served in the Ukrainian regiment "Azov" as a driver, commander of a vehicle platoon. He was dismissed. In the spring of 2022, Mizhgorodskyy was detained in Mariupol. He was accused of organising the activities of a terrorist organisation and forcible seizure or retention of power. Human rights activists note that he is a prisoner of war, so he should not have been held criminally liable actually for participation in hostilities, and in addition, they consider the charges absurd.