Euston Station has been hit with major disruption for the second day running because of a signal failure between Milton Keynes Central and Watford Junction.
It comes after a similar signalling fault on Tuesday at the station threw services into disarray, leaving some passengers stranded on stationary trains for up to two hours.
Passengers are being warned to expect disruption until the end of the day, with both Avanti West Coast services and London Northwestern Railway services affected. Trains may be cancelled at short notice or delayed by up to 80 minutes.
Meanwhile on TfL services, the Northern Line has no service between Golders Green and Edgware due to engineering works, while on the roads, the M25 is experiencing heavy traffic anticlockwise from J30 A13 (Lakeside / Purfleet) to J28 A12.
