Police closed the main road through Bulwark in both directions while emergency services dealt with the incident.
The tweet at around 2.20pm said: “Emergency services are dealing with an RTC on Bulwark RD in Chepstow from Lidl roundabout to the entrance of Lidls.
“Road is currently closed in both directions, diversions are in place which may cause congestion. Please find alternative routes for your journey.”
No further detail has yet been given about the incident, though emergency services were still in attendance some hours later.
One person speculated on Gwent Police’s Facebook post about the incident: “It looks seriously bad”.
