Rail passengers between Suffolk and London Liverpool Street are facing delays due to an earlier broken down freight train in Essex.
The troubled train came to a halt between Marks Tey and Kelvedon on the line heading towards the capital.
But the faulty train is now back on the move at a reduced speed.
Greater Anglia say disruption could continue until 11pm, with services being cancelled or delayed.
It is also having an effect on the Norwich-bound line, with the 9.30pm London Liverpool Street to Norwich service among the cancellations.
A full list of affected services can be found here.
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