A woman suffered a fractured skull and a broken arm after falling from a moving car.
The woman in her 20s fell from a Volkswagen Polo, on Hambridge Road, Newbury, UK at about 23:15 BST on Wednesday.
Thames Valley Police said a 38-year-old man had been arrested on suspicion of kidnapping and wounding/inflicting grievous bodily harm without intent.
The man from Bexleyheath, Kent, remains in police custody.
Police are appealing for witnesses to the incident and anyone with information, CCTV or dashcam footage to come forward. (BBC)