Passengers reported a series of huge collisions and a fire on board one train. At nearly two miles away from Paddington, the Intercity train was still travelling at speed. Early pictures showed just how widespread the devastation was. Some of the injured were treated beside the carriages. An injured victim is stretchered away from the scene.
Firemen hose down one of the smouldering carriages.
The smoke could be seen for miles around and the noise was heard by BBC staff a few miles away in the BBC News Centre.