Warsaw, 20 May 1950. Judge Janusz Gumkowski, acting as a member of the Main Commission for the Investigation of German Crimes in Poland, interviewed the person named below, who testified as follows:
| Forename and surname | Mieczysław Wisłocki |
| Date and place of birth | 12 November 1912 in Warsaw |
| Names of parents | Stanisław and Maria |
| Father’s occupation | butcher |
| State affiliation | Polish |
| Religious affiliation | Roman Catholic |
| Education | elementary school and a 3-year course at the Society for Vocational Study |
| Occupation | chauffeur |
| Place of residence | Ziemowita Street 48, flat 1 |
| Criminal record | none |
When the Warsaw Uprising broke out, I was in księcia Ziemowita Street, near no. 48. At the time, the Germans were stationed at Ziemowita Street 58, corner of Żmudzka Street. German units also occupied the school building behind the church. A German armored train was standing on the tracks. Young boys, or maybe insurgents, I do not know whether acting of their own accord or not, threw themselves at the train with bottles filled with petrol. The Germans surrounded them.
[Next] they started to round up men from all of the streets running from Ziemowita Street. The men were executed on the spot. They dragged the men out of the basement of the house at Przeworska Street 3/5 and executed them beside the wall at Ziemowita Street 42; it was said that six men were killed then.
I did not witness this, for I was hiding in my house at Ziemowita Street 48. Since the tracks are somewhat distant from our street, I did not see exactly what was going on there.
The armored train that the boys had attacked was standing more or less level with the [Gley?] factory. However, I did not notice whether the Germans were executing people near the factory.
I cannot state with certainty how many men died in our area at the time, but I think that not more than 20. As a matter of fact, there were very few men in our area on the day the Uprising broke out, because the Germans had deported many of them to Germany.
I did not hear about any other crimes committed by the Germans in our area during the Uprising.
At this point the report was concluded and read out.