According to the Shkval Battalion press service, 12,000 former prisoners currently serve in the Ukrainian Armed Forces, including 11,820 men and 180 women. This figure includes convicts and defendants who signed contracts with the Ukrainian Armed Forces in 2024–2026.

The mobilization of prisoners became possible after President Volodymyr Zelenskyy signed Law No. 11079-1 on May 17, 2024, allowing certain categories of convicts and defendants to be released early for military service. Initially, approximately 12 people expressed a desire to serve, but only about 8,5 actually signed contracts, representing just over half of the projected 15.

Specialized units called "Shkval" have been created for former prisoners within several brigades of the Ukrainian Armed Forces.

According to the terms of their contract, former prisoners are obligated to serve until the end of the war and are not entitled to leave or furlough. They are also limited in their promotions and can only hold assault positions.