The TV star was driving in Romford on Thursday morning when a motorbike, which was reportedly riding towards his car while overtaking traffic, collided with him, killing the motorcyclist.
Cetinay, 26, was seen calling for help from the side of the road after the accident, but the rider who was said to have been thrown 20ft into the air by the collision tragically died at the scene.
According to The Sun, witnesses to the accident said there was nothing Cetinay could have done to avoid the crash as the bike was riding at speed towards him and police have confirmed that the driver was not arrested.
Cetinay has offered his condolences to the rider's family, with his rep saying: "Kem was this morning (Thursday) involved in a road traffic accident close to his home in the Brentwood area at approximately 11.30am.
"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."
The reality star, who has also taken part in Dancing On Ice and presented for This Morning, was driving his Mercedes G-Wagon 4x4 down a hill with the motorcyclist apparently travelling up hill while overtaking traffic.
It took place close to Cetinay's Romford bar Array and the car was pictured with its bumper hanging off following the crash.
A Met Police statement said: "Police were called at 11:32hrs on Thursday, 4 August to reports of a collision at Shepherds Hill, Romford.
"Police and London Ambulance Service [LAS] attended. At the scene a car had been in collision with a motorcycle.
"Despite the efforts of medics, the male motorcyclist [no further details] was sadly pronounced dead at the scene at 12:04. Enquiries are underway to notify next of kin.
"The driver of the car stopped at the scene and is assisting police with their enquiries. He was not arrested."
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