Train services are expected to be disrupted until 9pm tonight, following delays between London Euston / Clapham Junction and Milton Keynes this morning.
Safety checks being made on the line between Hemel Hempstead and Watford Junction mean trains are having to run at a reduced speed between Milton Keynes Central and London Euston / Clapham Junction.
London Midland and Southern railways are no longer affected by this, but Virgin Trains will run a reduced service between Manchester Piccadilly / Birmingham New Street and London Euston.
Passengers may be delayed by up to 20 minutes.
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