The M1 has been closed in both directions between Barnsley and Hoyland following an overnight crash.
Emergency services were called to the scene between junctions 37 and 36 just after midnight, with the closure still in place.
National Highways said a car had left the carriageway, and warned there was “currently no estimated time of when the road will fully re-open”.
South Yorkshire Police said it was advising drivers to “avoid the area and plan an alternative route if possible”.
