Stevenage Train Station (Image: Archant)
A number of incidents, including broken down trains, are causing hour long waits from London stations.
Rail operator Govia, who operates Great Northern and Thameslink, are in the process of arranging a number of rail replacement buses from Letchworth, Baldock, Hitchin, Stevenage, St Albans, Harpenden, Welwyn Garden City, Hatfield and Potters Bar.
Disruption is expected to continue till 6pm.
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