Drivers have been warned that the road will be closed for 'some time'
The M4/M5 interchange at Almondsbury is reopen, but traffic is still slow following a serious crash earlier this morning.
Shortly before 7am, there was a collision between a car and a motorcycle.
A spokesman for Highways England said: "The motorway is likely to remain closed for some time and motorists are urged to find alternative routes."
There is no access from the M4 in both directions to the M5 southbound, with traffic being diverted.
Due to the crash, Highways are also unable to open the SMART motorway westbound between J19 and J20.
Drivers have been warned to face considerable delays all around Bristol this morning.
All lanes were reopened around 12:30pm, but there is still congestion following the incident.
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