Avon and Somerset Police are appealing for witnesses following a fatal collision on the M5 Northbound in Somerset.
The two-car collision happened at about 02:15 on Friday 21 December between Junctions 26, Wellington and 25, Taunton.
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, contact officers by visiting www.avonandsomerset.police.uk/contact or by calling 101 quoting reference 5218281062.