The series of sex attacks took place on the same residential roads less than five minutes’ walk from the station on consecutive weekends.
The first victim, a 30-year-old woman, was followed by the stalker and sexually assaulted on Fleetwood Road, Brent at 11.30pm on Saturday, August 28.
The second attack came a week later when a 21-year-old woman was followed by a male and sexually assaulted on Ellesmere Road at 10pm Sunday, September 5.
A person managed to stop the assault causing the suspect to flee the scene.
The third woman, 21, was sexually assaulted again on Ellesmere Road the next weekend at 10.15pm on Saturday, 11 September.
Again a member of the public stopped the attack and the suspect fled the scene.
Each victim described the man as mixed race with facial stubble, of slim build and wearing black clothing at the time of the assaults.
DI Jonny Newell, leading the investigation, said: “All of these assaults took place on a weekend, at a similar time and in very close proximity to both the underground and each other.
“It is clear that the perpetrator is waiting at or near the tube station with the sole purpose of seeking out women to follow to a secluded area before he carries out his attacks.
“On each occasion the victims have managed to raise the alarm, causing their attacker to flee the scene. We are incredibly grateful to the two members of the public who came to their assistance.
“All of the women have understandably been left shaken and we are doing everything we can to stop this happening again.
“We would urge anyone who lives in the area to think about whether they saw anything suspicious on any of these evenings and to check any CCTV or doorbell footage they may have.
Anyone with information should call 101, giving the reference 8659/11SEP.
Information can also be provided to Crimestoppers, anonymously, by calling 0800 555 111.
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