The High Speed train service has been disrupted today due to an emergency incident.
Southeastern says this happened between London St Pancras International and Ebbsfleet International, with all High Speed trains to and from St Pancras temporarily cancelled.
The line has since re-opened, but the operator is warning that cancellations, delays or revisions are still possible.
A spokesman for the train operator said: "Lines have reopened between London St Pancras International and Ebbsfleet International as the emergency services are now safely clear of the line.
"Trains may still cancelled, delayed or revised.
"This is expected until 1.30pm."
Southeastern was advising people to use alternative London stations.
The cancellations would also affect people travelling through stations such as Ashford International.
KentOnline is contacting the emergency services for further details.