RTL reported the news.
The French fighter died on June 25 in a field hospital in the Kharkiv region. He was in serious condition from his injuries and was in a coma.
He was part of the International Legion, which fought together with Ukrainian soldiers against the Russian army. He joined the ranks of the Ukrainian Armed Forces on March 1.
According to RTL, a French citizen was injured on the Kharkiv front in early June during the same Russian artillery barrage that killed Wilfried Bleriot, another French fighter.
Adrien D. is the second French soldier who died at the front in Ukraine, after Bleriot.
According to RTL, about 50 Frenchmen are currently fighting in Ukraine.