ALL trains at London Euston station have been cancelled or delayed with hundreds of commuters stranded.
The emergency services are responding to an incident and all lines are currently blocked.
Disruption is expected until the end of the day with delays of up to an hour.
Transport for London tweeted: “Due to trespassers on the railway at London Euston, all lines are currently blocked.
“Passengers are being advised to use alternative routes to complete their journeys.”
Eyewitness Danielle Louise said: “Trains stuck outside of London Euston with emergency lighting on, and Euston station is now closed.
“Hundreds of people waiting in the rain. It’s gonna be a long night!”
Another Twitter user added: “Something is going down in London tonight. Euston shut down due to ‘trespassing’ and undercover police margin around with the flashing blue light.”
TfL confirmed around 7pm: “All lines have reopened to and from London Euston following the trespasser having been removed.
“Trains will continue to be disrupted until the end of the day.”
Virgin Trains confirmed they have ticket acceptance in place with East Midlands Trains, West Midlands Railway, Chiltern Railway and London North Eastern Railway.
Southern Rail has also listed travel advice on their website.