UPDATE: February 18. 5.40pm

Gwent Police have confirmed that a 32-year old-man from Newport sustained life threatening injuries and remains at the Heath Hospital, Cardiff in a critical condition.

A spokeswoman said: "The vehicle involved left the scene.  

"It is believed to be a White Ford Transit Van.  

"Gwent Police are appealing to the public for any information that may assist with identifying and locating this vehicle."

Anyone who may have any information should call 101, quoting log: 44 17/02/2018.

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A MAN was seriously injured in the early hours of this morning in a crash on the A48 near Pwllmeyric, Chepstow.

The incident happened at around 2am.

A Gwent Police spokesman said "We are appealing for witnesses following a serious road traffic collision A48, Pwllmeyric, Chepstow which occurred around 0155hrs am on Saturday 17th February 2018.

"The collision involved a pedestrian and an unidentified vehicle which failed to stop at the scene.

"A 32-year-old male from Newport was seriously injured and is presently receiving treatment at the Heath Hospital, Cardiff.

"Anyone who may have witnessed the collision or may have any information relating to it is asked to call 101, quoting log: 44 17/02/2018."

A stretch of the A48 was closed while investigation work was carried out, but it has since reopened.

Newport Bus reported earlier that the A48 was closed in both directions between the Indian Empire restaurant, at Parkwall roundabout near Caldicot, to the Larkfield roundabout at Chepstow.

Services were affected but these have now returned to normal.