Police are investigating after a man was found critically injured at the side of a road.
Gwent Police were called to reports of a man who had been injured around 7.07pm on Monday (August 5) in the area of the B4245 between Rogiet and Undy.
A spokesman for the force said that a bicycle had been found in "close proximity" to the injured man.
He added that the man had been taken to the Royal Gwent Hospital with serious injuries and remains in a critical condition.
Gwent Police along with the Welsh Ambulance Service attended and officers remain at the scene for a number of hours.
The road was closed until Tuesday morning and diversions are in place.
The spokesman said: "Officers are now trying to establish the circumstances of this incident and are requesting any motorists using the road around this time to please check any dash cam footage that may provide further information that will assist officers with their enquiries."
They particularly want to speak to anyone who saw a cyclist between the Severn Tunnel Junction train station and the B4245 between 6.40pm and 7.10pm.
Anyone with any information or anyone who may have witnessed the incident is urged to contact Gwent Police on 101 or direct message them on Facebook or Twitter, quoting log 470 05/08/19
