Detectives investigating a stabbing that has left a teenager in hospital with a severe arm injury are appealing for information.
Officers were alerted to the incident just before 6pm on Sunday, 28 October, in the vicinity of West Hampstead Underground station, following reports of an altercation in a nearby street.
It is believed that the 17-year-old male victim of the attack left the tube station at around 5:54pm, followed by an unidentified man and a woman.
Shortly after this it is thought an altercation between the 17-year-old, and the male and female, occurred on West End Lane, during which the teenager sustained a serious stab wound to his arm.
The two suspects are believed to have fled the crime scene, then re-entered West Hampstead station without paying.
No arrests have been made at this time, and enquiries continue.
Detective Constable Rob Griffiths said: “This is a violent attack in which the victim has received very serious and potentially life-changing injuries. The motive for this attack is not yet known, although we have no evidence to suggest it is gang-related.
“We do not know if the victim and suspects were known to each other beforehand, or they met just prior to the attack. I am appealing for anyone with information to get in touch with police and provide us with any details they may have, however insignificant they might seem.
“We would particularly like to speak to a female witness, who we believe approached officers at the crime scene originally and could have vital information that might help progress our investigation. If you are this woman, we would ask you to please contact us again as soon as possible.”
Anyone with information is asked to contact police on 101 and quote CAD 6012/28Oct or call Crimestoppers anonymously on 0800 555 111.