The Harrow man killed in a high speed car smash has been named as 28-year-old Vasile Antonescu.
The Boxmore Road resident died intantly when the blue Vauxhall Calibra he was a passenger in careered into three parked cars a road island and a lamp post in Watford.
Police arrested the 23-year-old driver on suspicion of causing death by dangerous driving after he fled the scene.
The A41 North Western Avenue was close for a number of hours after the fatal smash, which took place at 1.30am on Sunday morning.
Police are still appealing for information.
DC Denise Rayner, from the Road Death Investigation Unit, said: "This is a tragic incident in which a young man has lost his life so it is important for establish what has happened.
"This collision occurred in the early hours of the morning and we have some witnesses, but we would like to speak to anyone that saw the Calibra before the collision, during the collision or when the driver left the immediate scene.
"I would strongly urge them to contact me."
Anyone with any information on this crime should ring DC Rayner via the non-emergency number 0845 33 00 222.