A trespass incident between Potters Bar and Welwyn Garden City means that some lines are currently closed.
As a result, Great Northern services running between these stations may be delayed.
This is expected until 02:00.
Customer advice:
One of the lines through Hatfield, in the direction of Welwyn Garden City, is blocked. Please check station screens for the latest information as your train may not call at the usual platform.
Trains running on the open lines will be running at caution, so will be delayed by up to 5 minutes.
If you're waiting on a train which is delayed between stations:
If your train is delayed between stations, please remain where you are and listen to announcements,or speak to staff for further information. Teams will get you moving as soon as possible. They are aware of your location, and they will be doing everything they can to help you continue your journey.
Please don't leave the train unless you are asked to do so. Other trains may still be moving in the area, and the track is also a very hazardous environment.
Can you tell me more about the incident?
A trespass incident has been reported in the Hatfield area.
As soon as trespassing is known about, the speed of trains in the area is reduced, as it's not safe to run services at their usual speeds when someone is on the track. Sometimes, we need to stop trains entirely. Emergency services and Network Rail responders will be attending to make sure the person is removed.
Trespassing on the railway is very dangerous. Trains run all day, every day - whether passenger trains, freight trains or specialist engineering work machines. It's not possible to be sure that you can hear when a train is coming, and in many cases, you won't see a train until it is very close to you.
There are also electrical systems and cables, slippery surfaces, steep drops and other hazards.
Network Rail manage the railway infrastructure, and they're working hard to educate everyone about these dangers and prevent people from accessing the track. You can see their latest safety campaigns here.
As well as the dangers, trespassing on the railway is also illegal, and obstructing the railway can carry severe penalties.
Check before you travel:
You can check your journey using the National Rail Enquiries real-time Journey Planner.
Compensation:
You may be entitled to compensation if you experience a delay in completing your journey today. Please keep your train ticket and make a note of your journey, as both will be required to support any claim.