On 27 May 1947, Rubin Adler appeared in the office of the police of the United Nations Relief and Rehabilitation Administration in Stuttgart, Western section no. 1002, camp no. 664, and made the following declaration in lieu of an oath:
Name and surname Rubin Adler
| Date of birth | 24 November 1909, Końskie (Poland) |
| Place of residence | Reinsburgstrasse 193, Stuttgart |
| Registered as | Displaced Person |
| Card number | G 0508387 3 |
| Untersturmführer | Kapke was the head of the "Ukrainians" in Radom. He was tasked with |
carrying out death sentences in the town and the surrounding area. I know of a case of the carrying out of such a sentence on the order of SS-Polizeiführer Böttcher in 1943. Some 130 members of the Jewish intelligentsia were executed. Their executioners were the above mentioned "Ukrainians", commanded by Kapke. I learnt the details of this event from Dola Frydman, who was among 12 people who were saved from among 130 convicts in order to tell other people in the ghetto about the murder.
On 8 November 1943, the ghetto was liquidated, and 2,000 people were brought to Szkolna Street. That labor camp was supervised by the "Ukrainians". On the day of moving there, Kapke gathered mothers and children and placed them in another barrack and on the same evening led them to Biała Street. Some pits were already waiting there and all these people were burnt alive in them. Women, children, and the elderly who were unable to work, herded there from all over the district, were all burnt in the same place. During the massacre its site was closely guarded, and all traces of the execution were later removed. Kapke was in charge of this action. The only person to survive was a 16-year-old called Blejwajs, who hid in a fireproof safe that happened to lie around at the execution site. He later returned to the camp and told us what had happened. Blejwajs now lives in the United States.
I declare, in lieu of an oath, that the above is true to facts. I am aware of the criminal liability for making false declarations. I am ready to appear before a court as a witness.