One lane is closed on the M5 in Gloucestershire in both directions between junction 12 for Quedgeley and 13 for Stroud after an accident involving two cars and a caravan.
It happened on the southbound side at 5.30am and one of the cars crossed over to the northbound carriageway.
Two lanes re-opened southbound at 10am but there is major congestion as a result of the crash.
There are queues southbound back to junction 11A for the Brockworth bypass and onto the A38.
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