Rush hour bridge closure after crash and spillage

Traffic monitoring service Inrix said: "Just before 16:30 all traffic was held.

"The closure has now been extended back to J21 to assist."

Traffic is also congested on the opposite side of the motorway due to onlookers and trapped traffic has been allowed past the scene.

The incident is having an impact on traffic travelling northbound on the M5 from Portishead, while the M4 is congested back to the M32 for Bristol.

A diversion is in place, rerouting motorists via the M48 Severn Bridge.