A fourth man has been arrested following the fatal stabbing of an 18-year-old model.
Tributes have been left at the scene
Sally Anne Bowman was subjected to what police called an horrific attack yards from her home in South Croydon, south London, early on Sunday.
A 26-year-old man was arrested early on Tuesday in Addiscombe, Croydon. Police are also questioning a 20-year-old man who was arrested on Monday.
Two men arrested on Monday, aged 25 and 26, were released on police bail.
Neighbours said they heard the screams of the 6ft blonde girl, who dreamed of being on the cover of Vogue magazine.
Detectives are refusing to say whether Miss Bowman was sexually assaulted and are continuing the search for a murder weapon.
They said they are not aware of any injunction orders for people to stay away from her and said they have CCTV footage of Miss Bowman on a night out with friends in Croydon hours before her body was found.
Family and friends have left floral tributes close to the spot where her body was found.
Det Ch Insp Stuart Cundy, who is leading the investigation, said: "It was a normal Saturday night and we don't know what happened between 2am and 6.30am."
Miss Bowman was a part-time model and hairdresser, as well as a student at the Brit School for performing arts in Croydon, where former pupils include music stars Morcheeba, Amy Winehouse and Katie Melua.
The local model agency where Miss Bowman was on the books described her as "somebody very special".
After taking part in the Swatch Alternative Fashion Week in April this year and before the allegations about Kate Moss's private life, she said: "I would love to be compared to Kate Moss because she is just so amazing.
"To be where she is one day would be brilliant."
Mr Cundy said she was from a very loving family.
Her stepfather and two stepsisters visited the scene on Monday but were too distressed to speak.
In a statement however, they said: "We love and miss her so much and wish to stress that if anyone has the slightest information about Sally Anne's death, even if they don't think it's important, please come forward."