(NBC News) — The family of a Marine veteran who disappeared fighting in Ukraine believe he is alive and being held as a prisoner of war, a spokesperson said. 

Grady Kurpasi, 49, has not been heard from since April 23, the spokesperson, Don Turner, said Saturday, adding that the family want answers about what happened to him.

When Kurpasi spoke with his family from Ukraine, Turner said, he was “in good spirits” and “felt like he was doing the right thing.” He added that Kurpasi, who did three combat deployments in Iraq, had traveled to Ukraine for “humanitarian” reasons.

Kurpasi, he said, was “just trying to help people in any which way possible.” His family believe “there is a good possibility he is a POW right now.”

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