Trains to Pembrokeshire via Swansea and Carmarthen are facing severe delays today, following a fatal incident near Port Talbot.
Two rail workers have died after being struck by a train on railway tracks between Bridgend and Port Talbot.
A spokesman for Network Rail said: “We are shocked and distressed to confirm that two members of our team lost their lives today in an accident involving a train.
"We do not currently know the details behind this dreadful accident and we are fully cooperating with the British Transport Police and Rail Accident Investigation Branch.
"Our thoughts are with the families of our colleagues and our members of staff who will be affected by this tragic loss, and we will provide all the support we can.”
British Transport Police (BTP) said officers were called to the scene shortly before 10am on Wednesday.
BTP Superintendent Andy Morgan said: "We are making a number of urgent enquiries to understand exactly what happened in the moments leading to this fatal collision.
"Very sadly two people have died and my officers are now working to identify them and ensure that their families are supported at this incredibly difficult time."
The Rail Accident Investigation Branch has been notified.
A BTP spokesman was unable to confirm whether or not the victims were railway workers, although it is not believed maintenance work is currently taking place on that stretch of track.
According to Transport for Wales, the mainline route between Swansea, Carmarthen and Pembrokeshire is experiencing severe delays following the incident.
To check journeys, visit the TfW website.
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