Siddur recovered in 2001 from a Polish man selling books outside of the Treblinka death camp. Scientific analysis revealed that the message in Yiddish on the front and back covers of the siddur was written in blood. The message reads, “My name is Caminka from Treblinka. Hashem will avenge the deaths of my little daughter, Sara Leah; my dear wife Shaindel.”
At Treblinka, most Jews were put to death immediately. The few left alive were put to work sorting the belongings of those sent to their death or doing other jobs. The small groups of people that remained alive were killed when a new group would arrive a week later. It is believed that the owner of this siddur acquired it while sorting the belongings of other Jews. He then used it to write his last message.
In August 1943, about 300 people escaped from Treblinka; two-thirds of the escapees were found a week later and shot to death. Siddur currently in the Shem Olam Museum.