Two rail workers have died after being hit by a passenger train between Port Talbot Parkway and Bridgend stations.
The pair were struck near Margam by the Swansea to London Paddington train at about 10:00 BST.
A third person was treated for shock at the scene, but was not injured, British Transport Police (BTP) said.
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."
Bill Kelly, the company's route managing director for Wales, added: "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."
He said the details of the incident were not yet known.
One passenger on board said an evacuation of the train began at about 12:40.
BBC
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