Answer
Treblinka, a notorious Nazi death camp during World War II, was mistakenly linked to John Demjanjuk based on eyewitness accounts. This false connection stemmed from the erroneous identification of Demjanjuk as "Ivan the Terrible," a cruel guard at Treblinka. However, subsequent investigations revealed that Demjanjuk was not, in fact, "Ivan the Terrible" and had no involvement with the atrocities committed at Treblinka.