An accident on one of the busiest routes into Cardiff has caused major delays throughout the morning.
One person was taken to hospital after the crash on the A4232 just after 8am.
The crash closed one lane of the southbound carriageway throughout the morning and congestion soon built back to the M4, on the motorway and around Cardiff city centre.
A spokesman for the Welsh Ambulance Service said that a patient had been taken to the University Hospital of Wales. Their condition is not yet known.
Cardiff Bus reported "severe congestion" in and around the city centre, and warned of delays and disruption to services.
A spokesman said: "Please allow extra time for journeys today."
As well as delays on the M4 around junction 33, traffic was also heavier than normal on the A48 Eastern Avenue, on the A470 North Road and on Newport Road.
Motorists heading towards the city centre for Christmas shopping will also have added to the congestion.
Weather conditions are not great across the region today with heavy rain forecast and high winds.
The Met Office forecast says: "After a dry start for many, heavy rain will quickly spread from the west, turning heavy and persistent through the afternoon. It will be windy with gales at times."
