There are delays of up to 30 minutes and some cancellations on trains in and out of Cambridge. There's no estimate as to how long it'll be until normal service resumes.
Abellio, who run the Greater Anglia rail line, has been named Train Operator of the Year at the annual national Rail Business Awards.
Greater Anglia train operator Abellio says it's made real steps in customer service and punctuality in its first year in charge.
Greater Anglia have apologised for the delays that have disrupted services today