(NewsNation) — In February, Russia invaded Ukraine, resulting in Europe’s largest refugee crisis since World War II.

Many Americans wanted to help the cause, including Harrison Jozefowicz, a veteran and former Chicago police officer.

Jozefowicz served with the US Army with tours in Afghanistan and as a Chicago police officer for three years. He quit the CPD earlier this year, just after the Russian invasion began, and co-founded the group, “Taskforce Yankee: Ukraine.”

“We would go to the front lines, the remote villages, where you didn’t see the larger NGOs, and then we would deliver supplies and medical training,” Jozefowicz said. “Then from there, we would take those same displacements or refugees and take them away from the front lines.”

Now back home, Jozefowicz is asking Americans to do more.

“The No. 1 thing to remember in Ukraine is that what people are now experiencing, especially foreign, private citizens, and especially some governments, is what we like to call ‘compassion fatigue.’ Where it gets hard for people to keep caring about a war that isn’t happening in their own backyard,” Jozefowicz explained. “So what we try to do is constantly remind people like, hey, there are still thousands of people fleeing previously held, Russian occupied territory. And the stories that come from those people are just astounding for what they’ve had to go through.”

NewsNation affiliate WGN contributed to this report.