ITV News has been speaking to Davina Payne, who drove past the crash minutes after it had happened.
Traffic was at a standstill past the Brynglas tunnels going Eastbound. The coach was situated between the slip road to Caerleon and the slow lane. I could see passengers standing around - some were still in the coach and there appeared to be a person still sitting behind the wheel. The whole of the front of the coach had been taken off - there was mangled and twisted metal everywhere. There was a white car in the fast lane at a right-angle across the motorway.
More top news
Andrea Byrne presents the third episode of Helimeds following the helicopter crews of the Wales Air Ambulance.
The heaviest of the rain clears overnight leaving a much drier and brighter picture for the weekend!
Thunder and lightning brought a warm and dry start to September to a soggy end. But how are we looking for the weekend?