A man died after sustaining a gunshot wound in a possible drive-by shooting, police said.
Officers were called to Harrow Road in west London at around 12.15am on Saturday following reports that a man had been shot, close to the junction with Sutherland Avenue.
Members of London Ambulance Service treated the victim, who was in his 20s, at the scene but he died at 12.53am.
A Metropolitan Police spokesman said: "We believe we know the identity of the deceased but await formal identification and confirmation that next of kin have been informed.
"A post-mortem examination will be held in due course."
Officers from the force's Trident team are investigating the death.
No arrests have yet been made.