Part of the M23 in Sussex closed on Friday afternoon (March 1), following a multiple-vehicle crash between junction 11 and junction 10.
The collision happened at around 4.40pm and involved around 15 vehicles.
Reports say six people were taken to hospital with many more injured.
There were severe delays on the M23 and A23 with diversions put in place, while the southbound and northbound carriageways were closed for emergency repair work to be carried out.
Ambulance staff used the K2 Leisure Centre in Crawley as a triage point to deal with the many walking wounded.
Weather conditions on Friday meant hazardous conditions on the roads as Sussex was hit with heavy downpours and hail.
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