According to one testimony, in the course of a murder operation carried out by German police in the Lwów ghetto around May 22, 1942, on the Jewish holiday of Shavuot, a number of Jews were taken to the Lwów fortress, in the city center, and shot to death there.
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Written Testimonies
From the Testimony of Chaim Yehuda Goldfinger, who was born in 1891:
…On the Sunday before Shavuot in 1942 a murder operation was carried out. People were caught on the street; some of them…were taken to the fortress. About 60 Jews were killed…