Officers were called to Claremont Lane at around 6:20am yesterday after several calls about a collision between the vehicles.
A 37-year-old man from Leatherhead was pronounced dead at the scene.
A 52-year-old man from Orpington has been arrested on suspicion of murder. He remains in custody at this time.
Senior Investigating Officer Detective Inspector Natalie Pearce said: “Our thoughts are with the victim’s family at this very difficult time. Our investigation is in the very early stages and a specialist team of officers are working around the clock to follow up enquiries. The road remains closed but we hope it will be re-opened later this evening.
“We are hoping to speak to anyone who may have witnessed the collision, anyone that may have any dashcam footage of the collision, or anyone who may have seen a red moped and a white Seat Ibiza in the area in the moments before the collision. We are especially interested in the manner of driving by these two vehicles.
“We have also referred ourselves to the IOPC due to previous police contact with the suspect.”
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