Most train services have been restored on the Heart of Wales Line between Shrewsbury and Swansea, after a derailment blocked the line between Llanwrtyd and Shrewsbury.
Network Rail said the incident had happened at about 07.30 yesterday, when one bogie of the 05.22 from Shrewsbury left the rails just outside Llandrindod station. It added that the derailment had been at low speed, and that an investigation had been launched.
The train had been running about 25 minutes late when the derailment occurred.
There were no reports of injuries or significant damage, but trains on the route were limited to the section between Swansea and Llanwyrtd, while buses replaced trains between Llanwyrtd and Craven Arms.
National Rail has warned that some disruption will continue today (Wednesday). The 04.20 from Shrewsbury to Llandrindod and the return working from Llandrindod at 05.50 were both cancelled, while the 15.17 from Shrewsbury to Swansea and the 17.01 from Llandrindod to Shrewsbury will also be replaced by buses.