told BBC News 24 he understood the circumstances of the crash were similar to those in the Potters Bar crash.
In that crash, in May 2002, seven people died and 76 were injured when poorly maintained points derailed a train.
"From what I understand, they have found these points in a similar condition to those at Potters Bar, with some missing nuts and the stretcher bar, which keeps the rails properly apart, apparently loosened," he said.
Surely rail maintenance technicians must have heard about slotted nuts and split pins, or Nyloc/Simmonds nuts?
With respect, at this stage it's pure speculation to assume that maintenance engineers are to blame, and we must be very careful not to do that. There are many possibilities, and I think we would do well to wait for the results of an official investigation.