A man in his 20s was taken to hospital after he was stabbed in the leg in Queensbury.
Emergency services were called to the scene of a "disturbance" in Streatfield Road, Harrow , on Thursday (August 31) evening.
Footage taken at the scene shows emergency services and flashing lights in the area, as a large section of the pavement outside the shops was tapped off.
A spokesman for the force said: "A man, believed to be aged in his 20s, was taken to hospital suffering a stab or slash injury to his leg.
"His injury is not believed to be serious.
"Detectives from Harrow CID are investigating."
The spokesman added: "A crime scene was put in place and a forensic examination was carried out.
"There has been no arrest at this stage."
Anyone with information is asked to call Harrow CID via 101. To remain anonymous call Crimestoppers on 0800 555 111.
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