Between August and November 1888, he murdered at least five women, all prostitutes, in or around London's East End's Whitechapel quarter. Jack the Ripper was never apprehended or identified. The murder locations are now the center of a macabre tourism business in London. Jack the Ripper killed five women in five months. A more violent individual could not be found in history. Although the murders have been subject to many theories, no one person has ever been convicted of them. The Whitechapel district of London is on the edge of the City of London; both areas are part of the E1 postcode district. Whitechapel is a neighborhood within the borough of Tower Hamlets. It is bordered by Mile End to the east, Stratford to the south, St Paul's to the west, and Aldgate to the north. The Whitechapel district is known for its large population of immigrants from eastern Europe. Many of these people work in the surrounding markets or factories. On 8 September 1888, Mary Ann "Polly" Nichols was walking home from her job as a charwoman when she was attacked by an unknown man. He stabbed her 41 times and left her body in an alley behind Pudding Lane. This is where the name "Jack the Ripper" came from.