On 22 November 1945 in Treblinka, Judge Z. Łukaszkiewicz interviewed the person named below as an unsworn witness. Having been advised of the criminal liability for making false declarations, the witness testified as follows:
| Name and surname | Karol Socha |
| Age | 42 |
| Names of parents | Franciszek |
| Place of residence | Treblinka |
| Occupation | Polish State Railways pointsman |
| Religious affiliation | Roman Catholic |
| Criminal record | none |
During the occupation, I worked at Treblinka railway station, where I still work. If I am not mistaken, transports of Jews had been arriving there since June 1942. These transports were most frequent until Christmas 1942, and there were days when as many as three transports arrived.
After New Year’s Day, the number of transports decreased significantly and I suspect that there were at most two transports per month. This state of affairs continued until the camp was burned down, and then, if memory serves me right, there were no more transports. Each transport was typically made up of 60 wagons, and in each wagon there were from 180 to 200 people. 20 wagons at a time were brought to the camp ramp because it couldn’t accommodate more.
Transports arrived from different parts of Poland and also from abroad: from Bulgaria, Czechoslovakia, Germany. Transports from abroad would arrive in passenger coaches. During stops at Treblinka station, the Ukrainian crew killed a lot of people on the transport, and on one occasion, a couple of platforms were filled with corpses.
The report was read out, after which the witness signed it on every page.