He is assisting the investigation as a “witness”, according to his agent.
Detectives from Met’s Serious Collision Investigation Unit are appealing for anyone who either witnessed the incident or has dashcam footage.
A statement by the Metropolitan Police said the police were called to an incident at around 11.30am on August 4 for a collision in Shepherds Hill.
Police and the London Ambulance Service attended the scene where a Mercedes car had been in collision with a motorcycle.
They said that despite the efforts of medics, a 28-year-old male motorcyclist was pronounced dead at the scene at around noon. Their next of kin have been notified.
It added that the driver of the car stopped at the scene and is currently assisting police with their enquiries. He was not arrested.
Detective constable Liz Carrey of the Met’s Serious Collision Investigation Unit said: “While our enquiries continue we would still like to hear from anyone who either witnessed this incident or has dashcam footage.
“We are building a picture of the circumstances surrounding the collision and urge anyone with information to get in touch.”
A spokesperson for Cetinay confirmed the TV personality was involved in a road traffic accident close to his home in Brentwood area at approximately 11.30am on Thursday.
They added: “Tragically, a motorcyclist died in the collision. Kem has been assisting the police and is being treated purely as a witness to the incident.
“Kem will be making no further comment on this matter aside to offer his deepest condolences, prayers and sympathies to the motorcyclist’s family and friends.”
Cetinay won ITV reality show Love Island in 2017 with his partner Amber Davis.
Anyone who witnessed this incident or has dashcam footage can call the dedicated witness line direct on 020 8597 4874.