A vehicle towing a trailer has overturned on the motorway near Stroud, bringing traffic to a halt.
The incident is southbound between junctions 13 and 14 of the M5.
All lanes have re-opened after the car was righted by highways teams.
A police spokesperson said: "We were called shortly before 12.25pm after a car ended up on its roof on the motorway near Junction 13 southbound.
"The driver was uninjured but the clear-up continues.
"No one else was injured."
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