The Portway has been closed this evening (May 7) due to a police incident.
Emergency crews are at the scene, and the route has been shut on the outbound carriageway at Bridge Valley Road.
Motorists have been warned to expect long delays.
Travelwest tweeted: “A4 Portway outbound closed at the Bridge Valley Road expect long delays due to a Police incident.”
Traffic monitoring site Inrix says: “A4 Portway Eastbound partially blocked, very slow traffic due to police incident near Clifton Suspension Bridge.
“Affecting traffic near the Bridge, passing Bristol.”
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