The M5 was closed for more than 12 hours after a serious police incident.
The northbound carriageway was shut between J22 Edithmead Interchange (Weston-Super-Mare and Bristol Airport A38) and J21 St George's Interchange (Weston-Super-Mare and A370).
The road was first closed at around 11pm on Tuesday (January 18) and remained shut for a police investigation until 12.30pm the next day.
National Highway initially said the road would be shut until at least 9am. At this time, its guidance was changed to say the carriageway will remain shut "for a protracted period of time".
The A371 was also shut near Banwell and the 126 and 51 First Bus services were diverted around the closure.
Avon and Somerset Constabulary have been contacted for more information about the nature of the incident.
A diversion was put in place marked with a solid triangle symbol on local road signs. Drivers were advised to leave extra time for their journeys.