Passengers are facing delays at Stansted Airport after balloons were caught on overhead electricity wires at Cheshunt.
Train services running to and from the Essex station have been delayed, revised or cancelled.
The disruption is expected to last until 3.30pm today, Friday September 6.
A spokesman for Greater Anglia said: "Due to balloons caught on the overhead wire earlier, train services between Liverpool Street and Hertford East, Bishops Stortford, Stansted Airport and Cambridge have been disrupted.
"Network Rail response team have removed the balloons and train services are able to run through.
"However there may still be delays alterations and cancellations."
For updates on train timetables see here.
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