The 21-year-old victim was hospitalised after being knifed in the head on Saturday evening.
Police were called by the London Ambulance Service shortly before 9.40pm on Saturday evening following reports of a stabbing in East Lane, Wembley.
Officers and paramedics found a 21-year-old man suffering from a stab wound to his head.
He was taken to a north London hospital with non-life threatening and non-life changing injuries.
A 25-year-old man fled the scene, but was later arrested nearby on suspicion of attempted murder. He is currently at a north London hospital being treated for minor self-inflicted injuries.
Officers from Brent CID are investigating and enquiries are ongoing.
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