A woman was seriously injured after a Christmas Day collision on the M1 at Wakefield.
Police are appealing for witnesses to the incident, which took place on the southbound carriageway between junction 40 (Ossett) and junction 39 (Durkar) at around 6.50pm.
It is understood that the incident occurred after a blue Vauxhall Zafira people carrier collided with the central reservation and came to rest in the carriageway.
A woman then got out of the Zafira and was struck by a grey Vauxhall Astra travelling in the same direction.
The woman, aged 50, from Wakefield, was seriously injured and is continuing to receive treatment in Leeds General Infirmary.
A 48-year-old man from the Zafira was arrested at the scene on suspicion of drink driving. He was later released under investigation.
The driver of the Astra was interviewed by voluntary attendance.
Anyone who witnessed the incident or the circumstances leading up to it, particularly anyone with relevant dashcam footage, is asked to contact West Yorkshire Police Roads Policing Unit via 101 quoting log number 1074 of December 25 or online via www.westyorkshire.police.uk/101livechat