Completed the following sentence: At the beginning of April 1945, a few weeks before the
<unk> <unk> <unk> <unk> <unk> <unk> <unk> ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ Sources pay tribute to his role in ensuring that when U.S. troops arrived early in May 1945 the Fortress of Mauthausen was handed over without a shot being fired from either side.<unk> Sources pay tribute to his role in ensuring that when U.S. troops arrived early in May 1945 the Fortress of Mauthausen was handed over without a shot being fired from either side. Katz worked as a doctor between 6 May and 7 June 1945, attending to his fellow survivors from the vast concentration camp, now employed not by the German military but by the American army of occupation.<unk> Katz worked as a doctor between 6 May and 7 June 1945, attending to his fellow survivors from the vast concentration camp, now employed not by the German military but by the American army of occupation.