Over-running engineering works have caused chaos for tens of thousands early morning commuters heading to London at the end of Bank Holiday weekend.
Services running from King's Lynn in Norfolk, Cambridge and Stevenage in Hertfordshire were all affected.
First Capital Connect has put in place a reduced emergency timetable after dozens of train services were cancelled during the morning.
Network Rail was working on the line at Alexandra Palace in north London over the weekend and there were problems discovered after testing.
Click below to watch a report by ITV News Anglia's Olivia Paterson
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