Commuters travelling between Milton Keynes Central and London may experience some cancellations for the rest of the day after overhead wires being damaged near Leighton Buzzard.
London Midland, Southern and Virgin trains may be affected by the cancellations, which are expected to last until midday.
Passengers faced delays of up to an hour and cancellations earlier today as one of the four lines was blocked.
A spokesman for London Midland said: “A freight train came to a halt under damaged overhead wires.
“This will affect Leighton Buzzard railusers for the remainder of the day.
“Trains are running on time now but some services are being cancelled. This is because the freight train is blocking one of the lines so we can’t run as many services as normal.”