Emergency services are at the scene of a train crash in Powys.
Transport for Wales said "an operational incident" meant the lines between Machynlleth and Caersws are blocked.
Dyfed-Powys Police has closed the main A470 trunk road in Talerddig and advised drivers to avoid the area.
Residents reported a large emergency services presence including road ambulances and an air ambulance.
A coastguard helicopter is also at the scene, as well as firefighters.
Mid and West Wales Fire and Rescue Service said it was called to reports of a train accident at 19:34 BST.
British Transport Police is understood to be in charge of the incident.
Transport for Wales says services between Shrewsbury and Aberystwyth will be cancelled until further notice, with a rail replacement in operation.
Due to road closures, trains are unable to call at Caersws station until further notice.
TfW and Network Rail are expected to issue a joint statement.