A man was left with serious injuries after he was attacked in a barber's shop.
The attack happened at approximately 2pm in Village Way East, Rayners Lane in the Raja Salon.
The victim was treated at the scene by the London Ambulance Service, who called the London Air Ambulance to take him to hospital.
The store, which is split down the middle and is also a TV repair shop, has been taped off by police.
The Harrow Times is awaiting an update from Harrow police.