Messerschmitt Bf.109G - Russian Liberation Army users.

Back in December 1943 an aerial squadron was formed in the Luftwaffe, named Ostfliegerstaffel (Russische), but they were disbanded after some anti-partisan missions where this squadron took the night harassment role in July 1944.
They were regrouped into the Störkampfstaffel 8 (Night Harassment Squadron 8) which was formed very late in the war, in April 1945 and their last mission took place on 13th April, when they attacked a Soviet bridgehead at Erlenhof,on the Oder river.
The commander of the KONR Air Force (the self-proclaimed Russian Liberation Army's Air Force) was Maj.Gen. Viktor Maltsev and some former Soviet aces served in this unit. The most notorious one was Semyon T. Bychkov. Bychkov was a veteran of the Winter and continuation war, who, in 1942, was re-assigned to the Eastern Front. In July that same year, his aircraft crashed and he was sentenced to five years in a labour camp, however, as pilots were running short in the war, and they were badly needed, his sentence was lifted on 1st October. By August 1943, he had participated in 16 air combats with a score of 17 German aircrafts. He was awarded with the title of Hero of the Soviet Union on 2nd September 1943. He was shot down later, in December 1943, by anti-air fire and was taken POW inconcious. After being recovered in a military hospital he was taken to a POW camp in Suwalki.
Later, in 1944 he agreed in becoming part of the Ostfliegerstaffel (Russische) squadron where he took part in various night-harassment missions around Dvinsk, in Latvia, and he was awarded the German Ostvolk Medal 2nd class. After such missions he became the squadron leader.
At the command of a Bf.109G-10 he took part in the squadron's last raid and, at the end of the war, he, together with other KONR members, surrendered to the 12th Corps of the American 3rd Army. In September 1945, he was transferred to Cherbourg, France, where he was handed over to the Soviets. On 26th August 1946 he was charged by the tribunal of the Moscow Military District and sentenced to death. The next day, he submitted an appeal for pardon, but it was rejected and the sentence was executed on 4th November. Later, on 21st March 1947 he was posthumously stripped of all honours that had been awarded to him by the Soviet Union.

Sources:
1. https://en.wikipedia.org/wiki/Russian_Liberation_Army
2. https://en.wikipedia.org/wiki/Semyon_Trofimovich_Bychkov
3. Salamander Books - The Complete Book of Fighters