Police are appealing for witnesses after a motorcyclist was left with life-changing injuries after a collision near Heathrow Airport.
The smash on the M4 happened at around 8:35pm on Thursday and involved two cars and a motorbike on the westbound carriageway near junction 4.
The motorcyclist, a man in his 40s, was taken to hospital where his injuries were assessed as life-changing.
Both drivers stopped at the scene. The driver of one of the cars, a 38-year-old man, was arrested on suspicion of drink driving and causing serious injury by careless driving.
He has since been bailed pending further enquiries.
Officers from the Roads Policing Unit would like to hear from anyone who witnessed the collision or has dash-cam footage of the incident.
Anyone who can help is asked to call 101 quoting CAD 7098/01Feb