Avon & Somerset Police are appealing for witnesses following a fatal collision on the M5 northbound in Somerset.
The two-car collision happened at about 2.15am on Friday 21 December between the junctions for Wellington (26) and Taunton (25).
One driver was taken to hospital with serious injuries and sadly died. His next of kin have been made aware.
The driver of the other vehicle has been arrested and remains in police custody.
If you were on the motorway at the time and witnessed the collision, or saw a white Audi A3 or a black Mini Cooper in the moments before it happened, please get in touch.
You can contact officers through www.avonandsomerset.police.uk/