THE M4 is closed in both direction from junctions 30 to 32 following a three car traffic collision.
Ques of traffic can be seen for miles in both directions whilst police try to deal with the incident.
South Wales Police have asked motorists to find an alternative route if possible.
A force spokesperson said: “The M4 is closed in both directions in Tongwynlais, Cardiff between junctions 30 and 32 due to a road traffic collision.
“Motorists, please take an alternative route while the incident is ongoing.”