The incident happened in Heathway near the junction with Ford Street at around 10.20pm yesterday (August 26)
Paramedics arrived with officers and the biker, in his 40s, was rushed to hospital with possibly life-changing injuries.
A 23-year-old man was arrested on suspicion of driving under the influence of drugs after officers found the car involved in the crash in Ford Road.
Motorcyclist left with life-changing injuries after crash with car in Dagenham
The man remains in custody.
Detectives continue to investigate the circumstances and want to hear from any witnesses.
A Met Police spokesperson said: “Police were called at 22:19hrs on Tuesday, 26 August to reports of a road traffic collision involving a car and motorbike in Heathway, near the junction with Ford Street, Dagenham.
“Officers and the London Ambulance Service attended and found the motorcyclist, aged in his 40s, injured. He was taken to hospital with possible life-changing injuries.
“The car was found in nearby Ford Road and a 23-year-old man was arrested on suspicion of driving under the influence of drugs. He has been taken into custody where he remains.
“Detectives from the Met’s Serious Collision Investigation Unit are working to establish the circumstances.
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“They would like to hear from anyone in the area who witnessed the collision or might have dash cam footage of the incident or the time leading up to it.
“Please call 101 or message @MetCC on X quoting CAD 8145/26AUG25.
“To remain anonymous, contact the independent charity Crimestoppers on 0800 555 111 or visit its website.”
A London Ambulance Service spokesperson said: “We were called at 10.18pm last night (26 August) to reports of a road traffic collision in Heathway, Dagenham.
“We sent two ambulance crews and an incident response officer to the scene.
“We treated a patient at the scene and took him to a major trauma centre as a priority.”
