On 18 February 1946, a hearing began in the case of US Technical Sergeant Shirley B. Dixon, accused of deliberately killing Captain Vassily Klementiev and causing serious injury to Senior Lieutenant Peter Salnikov.

The incident occurred on 16 January 1946, when the officers attempted to board an American military train – “The Mozart Express” – travelling from Munich to Vienna via the Soviet Occupation Zone in Austria.
Senior Lieutenant Nikolai Usarkov got in the carriage together with Klementiev and Salnikov at St. Pölten Station. During cross-examination, he testified that Dixon treated them rudely, pushed them out of the train, and then opened fire. Usarkov managed to escape unharmed after jumping out of the moving train.
According to the testimonies of other passengers (Sergeant Witt, Lieutenant Plan, Private First Class Engstrom), Technical Sergeant Dixon tried to get the Soviet soldiers off the train, which they had illegally boarded. Addressing the intruders in English, Dixon demanded that they jump out of the moving train. The Russians did not understand but headed for the exit nonetheless. Moments later, shots were fired.
There is a version that Soviet officers drew their guns after taking offence to being ordered off the train. But the American fired first – he admitted this fact at the trial.
On 21 February 1946, Dixon was acquitted. An American military court judged that the sergeant had done his duty and found no crime in his actions.
The Dixon case was the first involving the murder of a Soviet citizen by an American serviceman.
Sources:
“Setting Free the Bears” by John Irving
The newspaper “Pravda”, No. 49 (10131) from 27 February 1946
The New York Times, Vol. XCV, No. 32,171 from 22 February 1946