At approximately 2.09pm this afternoon, Gwent Police received a report of a serious road traffic collision on the M4, J23A towards the Severn Bridge involving two vehicles.
Officers along with the air ambulance and South Wales Fire and Rescue Service have attended the scene.
The Eastbound carriageway is currently closed.
Officers are reminding motorists that there is currently heavy traffic in the area and to plan an alternative route where possible.
Anyone who may have witnessed the incident is asked to call 101, quoting log number: 246 10/10/17.