A West Point graduate and former Army Ranger who honored his Ukrainian ancestry by defending the nation against Russian-backed separatists was killed in fighting near the border, according to reports.

Mark Gregory Paslawsky, a 55-year-old investment banker who was born in New York but had lived in Kiev for several years, was fighting with the volunteer Donbas Battalion in the town of IIovaysk on Tuesday when he suffered mortal injuries, according to Vice News. He died from his injuries a short while later. No details were available on how he incurred his injuries.

“He was saying that he was in pain and that he didn't want to die,” Maxim Dondyuk, a Ukrainian photographer embedded with the Donbas Battalion, told Vice News. “People were telling him he was going to be okay. I think it might have been possible to save him if we had medevac helicopters or ambulances, but all there was on hand were the battalion medics."

Paslawsky was part of Ukrainian forces that have been battling separatists for control of IIovaysk, about 37 miles from the Russian border. The Ukrainian fighters have been trying to seize the city in order to cut off the supply route from Russia to Donetsk, a separatist stronghold 30 miles west of Ilovaysk.

Paslawsky, who insisted on serving as a private despite his U.S. Army experience, was known by the codename "Franko."

Paslawsky had been interviewed by Vice News earlier this month while he was in the Lunansk region with the Donbas Battalion. He told the news site that he had decided to join the cause and fight against the Russian-backed separatist movement because of his family’s Ukrainian background and frustration over the Russian takeover of the Crimea peninsula.

"Given what I saw, the level of incompetence, the corruption, the lack of activity — I just decided that I needed to go and participate. If there was ever a time to help Ukraine, this was the time to do it," he said.

A West Point spokesman confirmed that Paslawsky had graduated from the military academy in 1981. He served a decade in the Army, but no other details were available.

He is survived by his mother, brother and a sister who will head to Kiev for his burial.

"We had discussions amongst ourselves and his friends in Ukraine and we came to the conclusion that he would want to be buried in Kiev," Mark's brother Nestor Paslawsky said to FoxNews.com, adding that he had last spoke to him a week ago.

"He seemed in good spirits," Nestor said. "He felt confident that there was going to be a resolution."

His brother added that he felt moved to join the fight during the Euromaidan protests.

"The events of the Maidan and the people inspired him," he said. "He thought this would be the best way he could participate."

Paslawsky was not married and did not have any children.

"No. I'm not crazy like that," he told Vice News when asked if he had a family back home. "If I did, I wouldn't be here."

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