[Jimbuna]

Officials say they assume both train drivers had no visual contact before the crash as the site is on a bend - and therefore crashed into each other largely without braking.
The stretch of line had an automatic braking system designed to halt any train that passed a stop signal. It is not yet known why this failed to stop the crash but two of the three data recorders or "black boxes" on board the trains have been recovered so they should have a clearer indication of what went wrong soon.