The reality star, who won the ITV dating show in 2017, is said to be “devastated” after his Mercedes G-Wagon collided with a motorbike in Romford, Essex on Thursday morning.
The motorcyclist was pronounced dead at the scene despite efforts from paramedics.
A source told MailOnline that Kem has been left “traumatised” by the incident and is cooperating with police.
“Kem is devastated about what's happened. He's a sensible driver; no one could have foreseen this tragic accident happening,” the insider said.
“There has been no wrongdoing on Kem's side, he's not at fault, and is being treated by police as a witness. He's still dealing with the shock alongside close friends and his family.”
A statement from the Metropolitan Police confirmed: “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.”
And in a statement, Kem's representative said: “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.”
Kem won the third series of Love Island back in 2017 with former girlfriend Amber Davies.
The pair called it quits four months after lifting the crown and scooping up the £50,000 cash prize but have remained friends since their split.