A former US Marine who spent more than two years imprisoned in Russia was wounded while fighting in Ukraine, the US State Department confirmed Tuesday.

Trevor Reed, who was released by Russia in April 2022 as part of a prisoner exchange deal, was transferred to Germany for treatment after suffering unspecified injuries while participating in the fighting alongside Ukrainian forces, according to US State Department spokesman Vedant Patel.

Patel stressed that Reid "was not involved in any activities representing the US government," stressing that he went to Ukraine to participate in the fighting by personal decision.

He revealed that Reid was taken to Germany with the help of a private non-governmental organization and is currently receiving medical care.

And US Secretary of State Anthony Blinken announced that he had no other information about Reed's condition or situation, but he again warned the Americans not to go to Ukraine.

"This confirms why we continue to call on the Americans not to travel to Ukraine and take part in the fighting there," he told a press conference during a visit to Tonga.

Blinken indicated that he does not expect Reed's case to have an impact on US efforts to return two Americans held in Russia, Ivan Gershkovich, a Wall Street Journal reporter, and Paul Whelan, a former US Marine.

"I expect that even as we deal with all kinds of other challenges in our relationship with Russia, we are ready and determined to continue working to bring Ivan and Paul home," he said.

Reid was a student at the University of Texas in 2019 when he went to Russia with his Russian girlfriend.

He was arrested on charges of assaulting law enforcement officers while intoxicated and sentenced to nine years in prison.

In April of last year, Russia released him after the White House negotiated a deal to exchange him for Konstantin Yaroshenko, a Russian pilot who was sentenced to 20 years in prison by a US court for drug trafficking.

White House spokeswoman Karen Jean-Pierre said the US government has been "extraordinarily forthright" in assuring citizens that they "should not travel to Ukraine, let alone participate in hostilities."

She indicated that she could not provide estimates of the number of Americans who might have volunteered to fight alongside the Ukrainian forces.

When asked if the Reed incident could complicate the efforts made by the United States to release other Americans imprisoned in Russia, according to Washington, Jean-Pierre said that they are "separate" cases.