One person is critically ill in hospital following a two-vehicle collision on the A48.
A Ford Fiesta car collided with a Ford Transit van near a section of the road known as The Tumble at around 6.40pm on Wednesday evening.
The road was closed both ways between the Culverhouse Cross roundabout and the Downs junction for nearly twelve hours.
Three people were taken to hospital - with one person suffering injuries which are described as life threatening.
A South Wales Police spokesperson said: "The circumstances surrounding the collision remain under investigation."
The road reopened at around 6.30am on Thursday morning.

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