The Jack The Ripper Letters - From London To Hell

The "From Hell" letter (also called the "Lusk letter") is a letter that was posted in 1888, along with half a human kidney, by a person who claimed to be the serial killer known as Jack the Ripper. The murderer killed and mutilated at least five female victims in the Whitechapel area of London over a period of several months, the case attracting a great deal of attention both at the time and since. The exact number of victims has never been conclusively proven, and the identity of the perpetrator of the Whitechapel killings has likewise remained unsolved.

Postmarked on 15 October 1888, the letter was received by George Lusk, then head of the Whitechapel Vigilance Committee, the following day. The message was accompanied by a preserved section of a human kidney; the letter's writer claimed to have eaten the other half of the organ. The police received a large number of letters claiming to be from the murderer, at one point having to deal with an estimated one thousand letters related to the case, but the "From Hell" message is one of the few that has received serious attention as possibly being genuine. Opinions on the matter have remained divided. Several fictional works have referred to the Lusk letter, an example being the thriller novel Dust and Shadow.
https://en.wikipedia.org/wiki/From_Hell_letter