A multi-vehicle accident led to the closure of the M1 this afternoon.
Police said three cars and a pick-up truck were involved in a collision just before 2pm.
It happened near junction 43 of the southbound carriageway where the motorway merges with the M621.
The southbound M1 was closed between junction 44 and 43 from 2pm to just after 3.30pm to allow the Yorkshire Air Ambulance to land.
A man who suffered head injuries was taken to Leeds General Infirmary by air ambulance.
Two lanes of the M1 southbound between junctions 44 and 43 have been re-opened while one lane remains closed.
Police said the slip road at Junction 7 of the M621 southbound remains closed.