The letter is widely believed to have been a hoax, and may have been written by a journalist in a deliberate attempt to heighten interest in the story. Other nicknames used for the killer at the time were "The hitechapel Murderer" and "Leather Apron". Attacks ascribed to the Ripper typically involved female prostitutes from the slums whose throats were cut prior to abdominal mutilations. The removal of internal organs from at least three of the victims led to proposals that their killer possessed anatomical or surgical knowledge. Rumours that the murders were connected intensified in September and October 1888, and letters from a writer or writers purporting to be the murderer were received by media outlets and Scotland Yard.
The "From Hell" letter, received by George Lusk of the Whitechapel Vigilance Committee, included half of a preserved human kidney, supposedly from one of the victims. Mainly because of the extraordinarily brutal character of the murders, and because of media treatment of the events, the public came increasingly to believe in a single serial killer known as "Jack the Ripper".