FIRST Capital Connect (FCC) has apologised to passengers for severe disruption on the Thameslink route this morning (Friday), including train cancellations.

A spokesman explained that the problem stemmed from a signal box fire alert at Three Bridges at about 5am. The Network Rail signal box controls the main line to Brighton.

Staff had to be evacuated and, the spokesman added, “as a result, nothing could move”.

While all lines have now reopened, passengers travelling from St Albans should expect delays of up to 15 minutes, last minute cancellations and changes to the number of carriages on the Thameslink line.

However normal service is expected to resume by midday today.

Network Rail has also apologised to passengers for the disruption.