Commuters are facing disruption on the trains this morning as a result of a points failure between London Euston and Watford Junction.
Some lines are blocked with Avanti West Coast services and London Northwestern Railway services into the capital affected.
National Rail says the disruption is expected until 8am.
Meanwhile the District line has been suffering severe delays between Edgware Road and Wimbledon due to a faulty train.
Follow the latest updates below...
Delays between London Euston and Watford Junction
07:03 , Michael Howie
Trains between London Euston and Watford Junction are suffering delays as a result of a points failure.
National Rail says trains running between these stations may be delayed by up to 25 minutes.
We'll keep you posted on all the major developments throughout the day.