There are currently severe disruptions to train services between Chester and Holyhead on Thursday afternoon.
This is due to a power failure affecting the signalling system.
BTP North Wales tweeted that "Disruption is severe" and that Network Rail are doing their best to rectify the issue.
"Due to a power failure affecting the signalling system, there are currently no trains running along the North Wales Coast currently," they added.
Network Rail said the fault with the signalling system at Llandudno Junction has resulted in all lines being blocked.
A spokesperson said: "Trains may be delayed by up to 50 minutes or cancelled until approximately 8pm.
Afternoon all.
— BTP North Wales (@BTPNorthWales) March 7, 2019
Due to a power failure affecting the signalling system, there are currently no trains running along the North Wales Coast currently.
Disruption is severe, but @networkrail are doing their best to rectify the issue. Please be patient with @tfwrail staff.
"Train services from Chester will be turning back at Rhyl.
"Train services from Holyhead will be turning back at Bangor."
The disruption is expected to last until 8pm.
Replacement road transport is being sourced to run on the following routes:
Between Bangor and Rhyl
Between Llandudno and Llandudno Junction, and between Llandudno Junction and Blaenau Ffestiniog.
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