A lorry driver has been arrested after a collision on the A467 at Risca.
Police arrested a 52-year-old man from Nottingham, on suspicion of dangerous driving after the collision on Tuesday morning.
The man is being held in police custody.
A 78-year-old man and a 74-year-old woman from Rogerstone were travelling in the car involved in the crash with the lorry.
Both are in a serious condition in hospital.
Anyone with information should contact Gwent Police on 101.