Police have arrested a 27-year-old man from Horsham following a pursuit on the A273 near Pycombe services.
It happened at around 2.20am this morning (December 8).
The man, driving a Ford Fiesta reached 'excessive speeds' leaving the road near the Ditchling junction and colliding with a wall.
The man was arrested at the scene for causing serious injury by dangerous driving, failing to stop, drug driving, and driving without a full licence and remains in custody at this time.
Two passengers were also in the vehicle at the time of the collision.
A man in his 30s suffered minor injuries, and a woman in her 20s sustained a serious leg injury which was assessed by paramedics at the scene.
She has attended hospital for further treatment.
An investigation is underway.
Police say a mandatory referral has been made to the Independent Office of Police Conduct (IOPC) as is standard practice for these matters.
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