The murders of Amelie Delagrange and Marsha McDonnell in south-west London are now being formally linked by the Metropolitan Police.
Marsha (left) and Amelie had similar appearances
Amelie, 22, was attacked on Twickenham Green in August, while Marsha, 19, was attacked in February 2003 near her home in Hampton.
Four similar attacks on women in the area are also connected, say police.
The Met says one of the reasons the attacks are being linked is because of similarities in the victims' profiles.
RECENT ATTACKS IN THE AREA
1: 8 January 2003, 17-year-old girl attacked
2: 4 February 2003, Marsha McDonnell, 19, killed
3: 18 April 2004, Edel Harbison, 34, attacked
4: 19 August 2004, Amelie Delagrange, 22, killed
Speaking after a news conference on Monday, Det Ch Supt Andy Murphy said the victims were all female and primarily blonde.
He said they had been struck with a heavy instrument, late at night and within a close geographical area.
He said it was important to keep an open mind about the attacks but for the purposes of the investigations, they were now being linked.
Mr Murphy stressed there were no forensic or personal links between the cases.
The team investigating the two murders will also investigate assaults on a 28-year-old in Hounslow Road, Feltham, on 23 August; an attack on accountant Edel Harbison, 34, in Twickenham on 18 April; an attack on 36-year-old Dawn Brunton in Hounslow on 5 November 2003; and an attack on a 17-year-old girl from the Strawberry Hill area of Richmond on 8 Jan 2003.
Miss Delagrange had come to London to improve her English and worked at a delicatessen in Richmond, south-west London.
Four men arrested in connection with her murder have been released on police bail.
Mr Murphy said: "The fact they are on bail does not mean they killed Amelie Delagrange. We haven't charged anybody."
Five people have so far been arrested and released by detectives investigating the murder of Marsha McDonnell.