The dog was the size of a calf so that, unlike smaller dogs, his shoulders reached to the buttocks and abdomen of a man of average size. For this reason he frequently bit his victims in the buttocks, in the abdomen and often, in the case of male inmates, in the genitals, sometimes partially biting them off. When the inmate was not very strong, the dog could knock him to the ground and maul him beyond recognition. But when the defendant Franz was not around, Barry was a different dog.

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When we arrived in Treblinka and the Germans opened the freight cars we beheld a horrible sight. The car was full of corpses. The bodies were partly decomposed by chlorine. The stench in the cars made those still alive choke. The Germans ordered everyone to get out; those still able to do so were half dead. Waiting SS and Ukrainians beat us and shot at us...

On the way to the gas chambers Germans with dogs stood along the fence on both sides. The dogs had been trained to attack people; they bit the men's genitals and the women's breasts, ripping off pieces of flesh. The Germans hit the people with whips and iron bars to spur them on so that they pressed forward into the "showers" as quickly as possible. The screams of the women could be heard far away, even in the other parts of the camp. The Germans drove the running victims on with shouts of: "Faster, faster, the water will get cold, others still have to go under the showers!" To escape from the blows, the victims ran to the gas chambers as quickly as they could, the stronger ones pushing the weaker aside. At the entrance to the gas chambers stood the two Ukrainians, Ivan Demaniuk and Nikolai, one of them armed with an iron bar, the other with a sword. They drove the people inside with blows... As soon as the gas chambers were full, the Ukrainians closed the doors and started the engine. Some 20-25 minutes later an SS-man or a Ukrainian looked through a window in the door. When they had ascertained that everyone had been asphyxiated, the Jewish prisoners had to open the doors and remove the corpses. Since the chambers were overcrowded and the victims held on to one another, they all stood upright and were like one single block of flesh. (Yad Vashem Archives 0-3/2140)

In front of the entrance to the gas-chambers there were usually several Ukrainians standing by with dogs, who cruelly drove the victims in, often wounding them with knives. The victims were driven into the gas-chambers with their hands up, so that as manymight be squeezed in as possible, and small children were piled on top.

An SS-man Hitreider specialized in killing infants, seizing them by the legs and killing them with one blow on the head against a fence ...

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When asked during his later trial how many people could be murdered in one day, Franz Stangl, Commandant of Treblinka, answered:

"Regarding the question of the optimum amount of people gassed in one day, I can state: according to my estimation a transport of thirty freight cars with 3,000 people was liquidated in three hours. When the work lasted for about fourteen hours, 12,000 to 15,000 people were annihilated. There were many days that the work lasted from the early morning until the evening . . . I have done nothing to anybody that was not my duty. My conscience is clear.' " 
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Pregnant women were problems

When the doors were opened, "the disfigured, bitten prisoners, with torn-off and ears lay on top of each other in the most varied posture." The bodies were then carried to the furnace to be burned. Sometimes, the people were not dead and began to revive in the fresh air, especially pregnant women. They were shot by the guards and burned like the others. Some 800-1000 bodies were burned at the same time. They would burn for five hours. The incinerator was operated twenty-four hours a day.
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