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SUSPECT: Francis Tumblety - One suspect is most likely to be the Ripper -
Dr Tumblety Jack the Ripper suspect.
Francis Tumblety, an American quack doctor. To me, he fits almost all the criteria perfectly, including the FBI profile of the killer. Unless "Saucy Jacky" was someone completely unknown and untapped by the police (which is profoundly possible), this guy has jumped to the head of the line. Besides, he lived in Boston for a few years...