Commuters are facing disruptions on Thursday morning due to a train crash near Watford, which is impacting services to and from Euston. Trains are running at reduced speeds towards Milton Keynes Central, resulting in potential delays of up to 45 minutes or service revisions. The affected lines include Avanti West Coast and London Northwestern Railway services between London Euston and various destinations, as well as Southern trains running between East Croydon and Hemel Hempstead. The disruption is expected to continue until 9 am.