Five vehicles were involved in a crash on the M11, police said.
Essex police were called to the motorway near Chigwell and Theydon Bois at 16:55 BST with National Highways East saying the stretch was “blocked northbound between junction five for Loughton and junction six for the M25”.
Traffic was held in both directions to allow an air ambulance to land at the scene, with drivers facing delays of about 60 minutes.
A spokesperson for the force said both sides of the carriageway were later reopened and thanked drivers for their patience.