Here are the admissions Jack the Ripper revealed about his crimes in disturbing letters, as a new DNA breakthrough may finally solve the 136-year case.

When it comes to true crime, no case is more famous than Jack the Ripper.

Active in the East London in the year 1888, the serial killer is said to have killed five women in the Whitechapel and Spitalfields areas, with a further five murders dating to 1891 possibly linked to the individual.

Any information after that and we’re solidly into people’s best guesses. Although it’s widely agreed the Ripper was a male and may have possessed some form of medical knowledge.

One of the prime suspects in the case is a man named Aaron Kosminski, a barber who had relocated to London from Poland and lived in the area at the time the murders were committed.

The Kosminski theory is widely supported by author Russell Edwards and has claimed to have DNA proof linking semen found on the shawl of one of Ripper’s victims to a descendant of the barber’s.

However, Edwards’ claims to have found the killer have been divisive, with subsequent reports claiming the DNA analysis conducted by Dr Jari Louhelainen had made a ‘serious’ error, which if corrected would link the sample to ‘more than 99 percent of people of European descent’.

Which, if true, means we’re once again back to ‘who do you believe’ arguments rather than anything based in scientific fact.

Disputes over the Ripper’s identity aren’t the only mystery about the case which baffled police, with various letters claiming to be from the killer also doing the rounds.

Most have since been confirmed to be hoaxes with only a handful – the ‘Dear Boss’ letter, the ‘Saucy Jacky’ postcard, and the ‘From Hell’ letter – having the potential to be legitimate.

The letters are all highly gruesome in nature, with the author even going to the lengths of attaching half of a human kidney to the ‘From Hell’ letter before sending it off.

Subsequent examinations of the kidney (via All That’s Interesting) revealed the owner was female, around 45 and suffered from a disease which can be linked to drinking. This matches up to fourth Ripper victim Catherine Eddowes, who was 46-years-old, a heavy drinker and found missing a kidney.

The infamous ‘Dear Boss’ letter (Public Domain)

The ‘Dear Boss’ and ‘Saucy Jacky’ letters are also equally gruesome in nature, with the former being the first of his letters, with part of it reading: “I am down on whores and I shant quit ripping them till I do get buckled.”

It’s also here the killer allegedly named himself ‘Jack the Ripper’ and made fun of speculation about his work background, “They say I’m a doctor now. ha ha.”

Meanwhile, the ‘Saucy Jacky’ postcard was smeared with blood and referred to the killings of Elizabeth Stride and Catherine Eddowes and added that he’d had no time to sever the ears in order to send to police.