After the morning rush hour
Just after the daily morning rush hour, the station became less congested, and the number of trains passing decreased. Normally, this was the point at which staff could exhale a sigh of satisfaction that everything had gone as planned for the day. However, not this morning.
Seeing something move
They received a call from one of the train operators who had just passed through the station. He reported seeing something move on the track. He hadn’t noticed it until he was quite close, and he was lucky that it was at that moment on the track going the other way.