Police hunting the killer of a teenage model are examining possible links with at least six sexual offences.
Sally Anne Bowman was stabbed in Croydon
Forensic scientists have already linked her murder to a sex attack which took place in Purley in 2001.
About half a dozen women have called the incident room since Sally Anne Bowman, 18, was stabbed to death in Croydon, south London, a week ago.
Detectives said the crimes reported ranged from indecent assault to "peeping Tom" offences.
Ms Bowman was sexually assaulted then murdered after a night out in Croydon.
Officers believe her killer may have committed other similar crimes and have appealed for women who have been the victim of a sexual offence, which may not have been reported, to come forward.
Det Ch Insp Stuart Cundy, said that police were trying to fill in the gap between the 2001 attack and the murder of Ms Bowman.
He said: "That is a gap of about four years and I believe that someone who has committed this horrific murder will have offended during the intervening time.
"There is always the possibility that this individual might have been in prison or abroad.
"I'm not going to discount that but if he was living locally, or working locally, he may have attacked other women."
Mr Cundy said they had not ruled out the possibility that some of Ms Bowman's possessions may have been taken by the killer as a "trophy".
Miss Bowman was wearing a white cardigan similar to this
Her white Prada handbag, a Samsung D500 mobile phone, a short white crochet bolero-style cardigan, Gucci purse and, possibly, her passport, are still missing.
He said: "We do know that offenders sometimes take trophies, but it could be that it was simply taken away and dropped."
Mr Cundy also said he thought the killer may have had blood on his clothing and a 12-14cm knife, possibly a kitchen knife or hunting knife, has not yet been recovered.
Since the killing, about 50-60 calls have been made to the incident room with some people giving names.
On Saturday night Ms Bowman's mother and sisters joined police in appealing to clubbers for information about her last few hours.
Her attacker is thought to be white, in his 20s or 30s, between 5ft 9in and 6ft and of medium build with short brown hair.