On 12 October 1945 in Łódź, Judge Z. Łukaszkiewicz heard as a witness the person specified below; the witness did not swear an oath. Having been advised of the criminal liability for making false declarations, the witness testified as follows:
| Name and surname | Jankiel Wiernik (Jan Smarzyński) |
| Age | born 1888 |
| Parents’ names | Icek |
| Place of residence | Łódź, Franciszkańska Street 15 |
| Occupation | construction entrepreneur |
| Religious affiliation | Judaism |
| Criminal record | none |
I came to Treblinka on 23 August 1942 with a transport from the Warsaw Ghetto. In Treblinka I worked as a master joiner/carpenter, and this is why I escaped death. As I was working in both parts of the camp, I had an opportunity to get to know well both the life in and the functioning of the entire camp.
During my stay there, an underground organisation was set up among the Jewish workers, with the aim to organise an uprising. As I had relative freedom of movement between the two parts of the camp, I was a liaison. On 2 August 1943 the uprising erupted, and it led to the destruction of the camp.
As a result of the uprising I managed to escape from the camp and get to Warsaw, where I still worked for independence organisations and took an active part in the Warsaw Uprising of 1944, as a gunman of the 1st Company of the Syndicalist Brigade (the witness produces a certificate no. 1200-II/25/S of 10 September 1944).
In winter 1943 I wrote down all my memories and experiences from Treblinka, which were still fresh in my memory, and at the beginning of 1944 my work was printed by underground organisations in Warsaw as a booklet titled “Rok w Treblince” [“A Year in Treblinka”].
I own one copy of this booklet and I hereby submit it so it may be copied and appended to my testimony. I confirm the contents of this booklet and I cannot add anything else with regard to this matter.
The report was read out and then signed by the witness.