[1] [2] The accident occurred on what was then a single-track rail line between Norwich Thorpe and Brundall.

The latter had left Norwich Thorpe at 21:30 and would normally have had a clear run on its way to Yarmouth, since the mail train should have been held on a loop line at Brundall to allow the express to pass.

Due to a series of errors (primarily, the telegraph clerk sending the authorisation message before it had been signed by the appropriate official), both drivers received their authority, and anxious to make up for lost time, set off at speed along the single track.

The accident, when it occurred around 21:45, resulted in both locomotives rearing into the air, and carriages reduced to wreckage.

Prompted by the accident, engineer Edward Tyer developed the tablet system in which a token is given to the train driver; this must be slotted into an electric interlocking device at the other end of the single-track section before another train is allowed to pass.