From the Daily Mail article:
[They were] investigating groups of people who may have been in Whitechapel at the time of the killings, which took place between August and November 1888. These included sailors as the district - famed for its prostitutes and taverns - is just a short distance from London's docks.
Gaps in the killings indicated the perpetrator had been a traveller. Feigenbaum had admitted he was overcome by the desire to mutilate women. And then there was his lawyer's dramatic statement after his execution at Sing Sing jail. 'I believe that Carl Feigenbaum, whom you have just seen put to death in the electric chair, can easily be connected with the Jack the Ripper murders in Whitechapel, London,' William Lawton told reporters.
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