An injured man was found in a Harrow garden this afternoon after being stabbed.
A police helicopter was called out following the incident on Harrow High Street.
The injured man, aged in his 20s, was found in Chester Drive.
London Ambulance Service also attended and treated the man for a hand injury, taking him to hospital.
Nobody else is believed to have been injured in the incident.
A Met Police spokesman said: "Police were called to Harrow High Street shortly after 1.30pm on Tuesday, September 11 to reports of a stabbing.
"Officers attended as well as the National Police Air Service (NPAS) and a search of the area was conducted.
"The man was located in the garden of a residential property in Chester Drive, Harrow, a short time later.
"We are not aware of any other injured persons and enquiries are ongoing to establish the full circumstances."
Police have confirmed that the injured man was arrested on suspicion of possession of Class B drugs with intent to supply and possession of an offensive weapon.