U.S. Marine veteran Mike Postupak watches as Ukrainian soldiers and civilians practice first aid at a training site outside Kyiv on Oct. 27, 2022. Postupak said he quit his private security job and put his life on hold to volunteer in Ukraine. (J.P. Lawrence/Stars and Stripes)

Oleksii Bozhko hefts a Ukrainian soldier as he demonstrates the firefighter’s carry, a method of lifting an injured casualty out of a dangerous area, during training outside Kyiv, Ukraine, on Oct. 27, 2022. Before the Russian invasion of Ukraine in 2022, Bozhko enjoyed spending his days kitesurfing on lakes and rivers. (J.P. Lawrence/Stars and Stripes)

Angel Luna, an American veteran who traveled to Ukraine after the Russian invasion in 2022, shows off his tattoo, which reads “Protect Freedom, not just for your country but for all,” while at a training site outside of Kyiv on Oct. 27, 2022. Luna, who served in the North Carolina National Guard, quit his job in a Walmart warehouse in Nebraska to join Task Force Yankee Ukraine in May. The task force provides humanitarian aid and medical training to Ukrainians. (J.P. Lawrence/Stars and Stripes)

Ukrainian soldiers and civilians practice first aid under the watchful gaze of instructors at a training site on the outskirts of Kyiv, Ukraine, Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)

Combat medic Natalya Luchko teaches a class of civilians how to place a tourniquet on a bleeding casualty at a training site outside Kyiv, Ukraine, on Oct. 27, 2022. Before becoming a first aid instructor, Luchko searched for her husband, who had disappeared fighting Russian forces in the east of Ukraine. (J.P. Lawrence/Stars and Stripes)

Ukrainian special forces soldiers jump from their seats and dive onto the floor as they rush to put on tourniquets during first aid training at a site outside Kyiv, Ukraine, on Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)

Ukrainian military medics take an exam that would allow them to instruct others on combat first aid on Oct. 27, 2022, at a training site outside Kyiv, Ukraine. Medics rotate back to Kyiv so they can share combat experience from the front lines with new soldiers and civilians. (J.P. Lawrence/Stars and Stripes)

Nikoleta Dimitrulina instructs a class of Ukrainian civilians on combat first aid at a training site on the outskirts of Kyiv, Ukraine, on Oct. 27, 2022. Dimitrulina evaluated how her students placed casualties on their sides into the recovery position, which helps prevent unconscious patients from suffocating. (J.P. Lawrence/Stars and Stripes)

Mike Postupak, an American volunteer for Task Force Yankee Ukraine, a group that provides humanitarian aid, observes as Ukrainian soldiers practice first aid at a training site outside Kyiv, on Oct. 27, 2022. Postupak is chief of operations in Kyiv and eastern Ukraine for the group, which mostly consists of military veterans and offers medical training. (J.P. Lawrence/Stars and Stripes)

Masha, a Ukrainian woman who declined to give her last name, learns first aid at a training site outside Kyiv, on Oct. 27, 2022. Masha said she lived through chaos during the Russian invasion, which happened as she visited Mariupol, where her parents live. She said she wanted to know first aid so she’s better prepared for war in the event she experiences it again. (J.P. Lawrence/Stars and Stripes)

Red lights flash and the sounds of explosions and gunfire blare from loudspeakers as Ukrainian civilians learn how to conduct first aid under stressful conditions at a training site on the outskirts of Kyiv, Ukraine, on Oct. 27, 2022. Among the students is Masha, (center), a Ukrainian woman who declined to give her last name. Masha said she escaped Mariupol after the Russian invasion of Ukraine in 2022. (J.P. Lawrence/Stars and Stripes)

A Ukrainian woman prepares to lift a casualty and move him out of danger as part of first aid training for civilians, in a room designed to mimic the stresses of war in Kyiv, Ukraine, on Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)

A Ukrainian soldier moves with his squad under simulated fire to retrieve a casualty during training at a site on the outskirts of Kyiv, on Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)

A Ukrainian soldier covers for his squad under simulated fire as they retrieve a casualty during training at a site on the outskirts of Kyiv, on Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)

Ukrainian soldiers gather to practice combat first aid at a training site on the outskirts of Kyiv, on Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)

Ukrainian soldiers gather to practice combat first aid at a training site on the outskirts of Kyiv, on Oct. 27, 2022. (J.P. Lawrence/Stars and Stripes)