There are major disruptions to train services in Cambridge and Stansted.
Due to electrical supply problems, services into Cambridge, Harlow, Stansted and Bishop's Stortford have been heavily affected.
Nine services between London Liverpool Street and Cambridge are affected.
Train services from Liverpool Street to Stansted Airport will run as far as Bishop's Stortford. Liverpool Street to Cambridge services are able to run but with severe delays.
Buses are being arranged to operate between Bishop's Stortford and Stansted Airport.
Passengers may also travel on Great Northern services via Kings Cross to Cambridge. Greater Anglia tickets will be accepted on that route Please allow an extended journey time of 60 minutes.
A further six services between Stansted Airport and Harlow Town will also be affected due to the electrical supply problems meaning some lines are blocked.
Train services running to and from these stations may be cancelled, delayed or revised. Disruption is expected until further notice.
Network Rail engineers are on site investigating.
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