A man was slashed across the face in front of shoppers in a high street.
Police say the victim, around 20-years-old, was slashed across the face and arm and officers were called to the scene 4.45pm yesterday, in Stanmore.
The man collapsed outside florist Dawn Flowers, in The Broadway, and he was taken by the London Ambulance Service to hospital where he remains in a stable condition.
His injuries are not believed to be life threatening.
The scene was taped off by Harrow police who are investigating the incident and are calling for anyone with any information to get in contact.